SOUTH GALWAY – GORT LOWLANDS
FLOOD RELIEF SCHEME
TENDER DOCUMENTS:
PROJECT BRIEF
AUGUST 2017
GALWAY COUNTY COUNCIL
ROADS, TRANSPORTATION, MARINE AND GENERAL SERVICES
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TABLE OF CONTENTS
1 BACKGROUND AND SCOPE OF SERVICES REQUIRED ............................................................................................ 1
1.1 Background ...................................................................................................................................................... 1
1.1.1 General Background .......................................................................................................................................... 1
1.1.2 Background to the Project ................................................................................................................................. 1
1.2 Project Objectives, Definitions and Scope ........................................................................................................ 2
1.2.1 Project Objectives .............................................................................................................................................. 2
1.2.2 Definitions ......................................................................................................................................................... 4
1.2.2.1 Principle Study Area – See Figure 1 ................................................................................................................ 4
1.2.2.2 Areas of Potential Significant Risk .................................................................................................................. 5
1.2.2.3 Flood Risk Management Plan ......................................................................................................................... 5
1.2.2.4 Watercourses .................................................................................................................................................. 5
1.2.3 Scope of Services ............................................................................................................................................... 5
1.3 Project Structure and Programme .................................................................................................................... 9
1.3.1 Project Structure ................................................................................................................................................ 9
1.3.2 Project Programme .......................................................................................................................................... 10
2 GENERAL REQUIREMENTS ................................................................................................................................. 11
2.1 Objectives and Scope of Works ...................................................................................................................... 11
2.2 Required Level of Detail ................................................................................................................................. 11
2.3 Management Arrangements ........................................................................................................................... 11
2.3.1 Project Management ....................................................................................................................................... 11
2.3.2 Steering Group Meetings ................................................................................................................................. 11
2.3.3 Progress Reports .............................................................................................................................................. 12
2.4 Use of Digital Media and GPS ......................................................................................................................... 12
2.5 Health and Safety Requirements .................................................................................................................... 12
2.5.1 General and Legal ............................................................................................................................................ 12
2.5.2 Safety Statement ............................................................................................................................................. 13
2.5.3 Appointment of PSDP ...................................................................................................................................... 13
2.5.4 On-site activities to be undertaken by the Consultant .................................................................................... 13
2.5.4.1 Safety Meeting .............................................................................................................................................. 13
2.5.4.2 Hazard and Risk Assessment ......................................................................................................................... 13
2.5.4.3 Accidents and Dangerous Occurrences ........................................................................................................ 14
3 DATA COLLECTION ............................................................................................................................................ 15
3.1 Level of Detail ................................................................................................................................................. 15
3.2 Relevant Datasets ........................................................................................................................................... 15
3.3 Flood Event Data Collection ............................................................................................................................ 16
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4 SURVEYS ........................................................................................................................................................... 17
4.1 Property Survey .............................................................................................................................................. 17
4.1.1 Data Requirements and Availability ................................................................................................................ 17
4.1.2 Consultant Duties ............................................................................................................................................ 17
4.2 Valuation Survey ............................................................................................................................................ 17
4.3 Channel And Structure Survey ........................................................................................................................ 18
4.3.1 Data Requirements & Availability .................................................................................................................... 18
4.3.2 Consultants’ Duties .......................................................................................................................................... 18
4.4 Flood Defence Asset Survey............................................................................................................................ 18
4.5 Map Information ............................................................................................................................................ 19
5 HYDROLOGICAL ANALYSIS BEING REVIEWED .................................................................................................... 20
5.1 Level Of Detail ................................................................................................................................................ 20
5.2 Review And analysis of Historic Floods ........................................................................................................... 20
5.3 CATCHMENT BOUNDARIES .................................................................................................................................... 20
5.4 Analysis of Hydrometric and Meteorological Data.......................................................................................... 21
5.4.1 Rainfall Data..................................................................................................................................................... 21
5.4.2 Hydrometric Data Review ................................................................................................................................ 21
5.4.3 Hydrometric Gauging Station Rating Reviews ................................................................................................. 21
5.5 Estimation of Design Flood Parameters .......................................................................................................... 21
5.5.1 Design Event Probabilities ............................................................................................................................... 22
5.5.2 Design Event Flow Estimation Methods .......................................................................................................... 22
5.5.3 Hydrological Estimation Points ........................................................................................................................ 22
5.5.4 Hydrological Calibration and Validation .......................................................................................................... 22
5.5.5 Sensitivity Tests ............................................................................................................................................... 22
5.6 Future Environmental and catchment Changes .............................................................................................. 22
5.7 Hydro-Geomorphological Assessment ............................................................................................................ 22
5.8 Hydrology Report ........................................................................................................................................... 23
6 HYDRAULIC ANALYSIS ....................................................................................................................................... 24
6.1 Level of Detail ................................................................................................................................................. 24
6.2 Development of Fluvial Hydraulic Models ...................................................................................................... 24
6.2.1 Fluvial Model Development ............................................................................................................................. 24
6.2.2 Fluvial Model Calibration ................................................................................................................................. 24
6.2.3 Fluvial Model Design Runs ............................................................................................................................... 25
6.3 SENSITIVITY TESTS .......................................................................................................................................... 25
6.4 FLOOD HAZARD MAPPING.............................................................................................................................. 25
6.4.1 Level of Detail .................................................................................................................................................. 25
6.4.2 Flood Mapping Requirements ......................................................................................................................... 26
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6.4.3 Degrees of Confidence..................................................................................................................................... 27
6.4.4 Formats for Delivery of Flood Hazard Maps .................................................................................................... 28
6.5 Option Evaluation ........................................................................................................................................... 28
6.6 Hydraulic Report ............................................................................................................................................ 28
6.7 Flood Mapping Report .................................................................................................................................... 29
7 FLOOD RISK ASSESSMENT ................................................................................................................................. 30
7.1 Flood Risk receptor Groups ............................................................................................................................ 30
7.1.1 Social Risk ........................................................................................................................................................ 30
7.1.2 Risk to the Environment .................................................................................................................................. 30
7.1.3 Risk to Cultural Heritage .................................................................................................................................. 30
7.1.4 Risk to the Economy ........................................................................................................................................ 31
7.1.5 Indicators of Vulnerability ............................................................................................................................... 31
7.2 Reporting of Flood Risk Indicators .................................................................................................................. 31
7.3 Flood Risk Maps ............................................................................................................................................. 31
7.3.1 Specific Flood Risk Maps .................................................................................................................................. 32
7.3.1.1 Indicative Number of Inhabitants ................................................................................................................. 32
7.3.1.2 Types of Economic Activity ........................................................................................................................... 32
7.3.1.3 Economic Risk Density .................................................................................................................................. 32
7.3.1.4 General Flood Risk Maps .............................................................................................................................. 32
7.4 Flood Risk Management Objectives ................................................................................................................ 33
8 ENVIRONMENTAL ASSESSMENT ........................................................................................................................ 34
8.1 Environmental Impact Assessment ................................................................................................................. 34
9 CONSULTATION AND ENGAGEMENT ................................................................................................................. 35
10 DEVELOPMENT OF FLOOD RISK MANAGEMENT OPTIONS ................................................................................. 36
10.1 Level of detail ................................................................................................................................................. 36
10.2 Preferred Design Standards ............................................................................................................................ 36
10.3 Flood Risk Management Methods .................................................................................................................. 36
10.3.1 Flood Forecasting Systems .............................................................................................................................. 37
10.3.2 Strategic Sustainable Urban Drainage Systems ............................................................................................... 37
10.4 Screening of Possible FRM Methods ............................................................................................................... 38
10.5 Development of Potential Options ................................................................................................................. 38
10.6 Appraisal of potential Options ........................................................................................................................ 38
10.7 Selection of Preferred Options ....................................................................................................................... 39
10.8 Spatial Planning and Impacts of Development ............................................................................................... 40
10.9 Draft Final report ............................................................................................................................................ 40
11 PREPARATION OF A FLOOD RISK MANAGEMENT PLAN ..................................................................................... 42
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11.1 Flood Risk Management Plan ......................................................................................................................... 42
11.2 Submission of Flood Risk Management Plan .................................................................................................. 43
12 REPORTING AND DELIVERABLES ........................................................................................................................ 44
12.1 Reporting Standards ....................................................................................................................................... 44
12.2 Deliverables.................................................................................................................................................... 44
Appendices
APPENDIX A – PRELIMINARY RISK ASSESSMENT FOR SITE WORK
APPENDIX B – REGISTER OF RELEVANT REPORTS
APPENDIX C – ASSESSMENT OF POTENTIAL FUTURE SCENARIOS
APPENDIX D – CALCULATION OF ECONOMIC DAMAGES AND COST BENEFIT ANALYSIS
APPENDIX E – SCREENING FOR APPROPRIATE ASSESSMENT AND EIAR TECHNICAL SPECIFICATION
APPENDIX F – PUBLIC AND STAKEHOLDER CONSULTATION
APPENDIX G – FLOOD MANAGEMENT METHODS
APPENDIX H – SCHEME DOCUMENTATION
APPENDIX I – CONFIRMATION DOCUMENTS
APPENDIX J – PROJECT MANAGEMENT SERVICES
APPENDIX K – GUIDE TO PROCEDURES AND OFFICES FOR TITLE RESEARCH
APPENDIX L - TRINITY COLLEGE DUBLIN RESEARCH AND MODELLING
APPENDIX M - MAPPED DETAILS FOR SCHEME
APPENDIX N - FLOOD DEFENCE ASSET SURVEY REQUIREMENTS
APPENDIX O - ASSESSMENT OF DEGREES OF CONFIDENCE
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GLOSSARY
AEP Annual Exceedance Probability (expressed as a percentage)
APSR Areas of Potential Significant Risk
CFRAM Catchment Flood Risk Assessment and Management
DoEHLG Department of Environment, Heritage and Local Government
DTM Digital Terrain Model (often referred to as ‘Bare Earth Model’)
EPA Environmental Protection Agency
FRA Flood Risk Assessment
FRMP Flood Risk Management Plan
GCC Galway County Council
HEFS High-End Future Scenario
HEP Hydrological Estimation Point
IRR Individual Risk Receptors
MRFS Mid-Range Future Scenario
NPV Net Present Value (in terms of CBA)
OPW Office of Public Works
SGFRC South Galway Flood Relief Committee
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1 BACKGROUND AND SCOPE OF SERVICES REQUIRED
1.1 BACKGROUND
1.1.1 General Background
Flood risk in Ireland has historically been addressed through the use of structural or engineered solutions (arterial
drainage schemes and/or flood relief schemes). In line with internationally changing perspectives, the Government
adopted a new policy1 in 2004 that shifted the emphasis in addressing flood risk towards:
A catchment-based context for managing risk,
More pro-active flood hazard and risk assessment and management, with a view to avoiding or minimising future
increases in risk, such as that which might arise from development in floodplains,
Increased use of non-structural and flood impact mitigation measures.
Notwithstanding this shift, engineered solutions to manage existing risks are likely to continue to form a key component
of the overall national flood risk management programme and strategy. A further influence on the management of flood
risk in Ireland is the ‘Floods’ Directive2 [2007/60/EC]. The aim of this Directive is to reduce the adverse consequences of
flooding on human health, the environment, cultural heritage and economic activity.
1.1.2 Background to the Project
Galway County Council and the OPW having recognised the significant flood risk that exists in South Galway, as
evidenced by the flooding in winter 1994/1995, 2009, 2014 & 2015/16 are progressing a flood relief scheme for the
affected areas and the required studies for adjacent upstream and downstream areas.
Following a reoccurrence of major flooding in 1994/95, the OPW commissioned an extensive report on flooding in the
South Galway Area. Jennings O’Donovan produced a report in April 1998 which included an examination of the flooding
problem, hydrological/hydrogeological processes, effects of climate change, environmental concerns/impacts and an
examination of works that could be undertaken to alleviate future flooding. The report included an examination of a
possible engineered overland flood overflow channel between Coole Lough and Kinvarra. A review in 2010 of the fully
engineered channel proposal, estimated the cost of provision at €48m, excluding VAT. The channel proposal was
unviable from a CBA perspective and judged to be unlikely to meet with approval from an ecological perspective.
Following a review of the floods events in 2009, a number of restoration works identified in previous reports were
undertaken. These works sought to restore previous natural flows, where it was felt human intervention had caused
restrictions:
A number of undersized and defective culverts were substantially upgraded to facilitate modelled and observed
flows through adjacent upstream and downstream culverts and bridges.
New culverts were installed on natural flood paths where roads had been raised above natural contours and
insufficient allowance had been made for flood flows.
Minor clearance works have been undertaken around selected swallow holes.
Notwithstanding the works undertaken, the record levels of rainfall that were recorded over a prolonged period in
2015/2016, resulted in Coole turlough flooding to a depth of 1m above the record levels of 2009, equivalent to 20%
1 Report of the Flood Policy Review Group, OPW, 2004 (www.opw.ie/about/fr_public.htm) 2 Directive on the assessment and management of flood risks, 2007/60/EC
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volumetric increase in storage within the turlough. This resulted in unprecedented levels of flooding to homes and lands
throughout the Lowland area.
The intensity and duration of rainfall experienced in the six flood events of the last twenty years cannot be routed
through the network of existing subterranean conduits to Galway Bay. The resultant uncontrolled overflow of the
network is a cause of extreme annual concern to the residents and farming communities in the area. A total of 20
households and businesses were flooded in the recent event and an additional 20 households were at serious risk of
flooding with many households reliant on sandbags and an enormous community effort to prevent flooding. In some
cases these efforts extended to weeks.
Further mitigation works on the network have been suspended, as the effect of these works on other areas of this
unique and complex network has not been fully assessed. This project will involve a full examination of all elements
effecting flooding in the area from source to discharge and will determine a programme of works to be undertaken. The
project will take account of all works and measures undertaken to date.
The combination of river water, groundwater, swallow holes and turloughs in the karst Gort Lowlands catchment, makes
this area unique on an international level from an ecology perspective and this is evidenced by the number of Designated
Areas (SACs, SPAs and pNHAs) attributed to the catchment, see Appendix M(2). The complexity of the flow network
within the catchment has justified an ongoing collaborative study between Geological Survey Ireland and University of
Dublin Trinity College which will greatly assist in the formation of the hydrological and hydraulic analysis of the scheme
(see Appendix L).
This project will involve the assessment and development of a flood relief scheme (a ’Scheme’) and other measures to
manage the existing flood risk in Gort Lowlands, and also the potential for significant increases in this risk due to climate
change, ongoing development and other pressures that may arise in the future. GCC will commission a Contract,
hereafter referred to as the ‘Project’ that shall comprise five stages, as set out below:
Stage I Feasibility Study and Preparation of a local Flood Risk Management Plan (see 1.2.2.3) and General Scheme
Development
Stage II: Public Exhibition
Stage III: Detailed Design & Confirmation
Stage IV: Construction Stage
Stage V: Handover of Works and Closeout
It is envisaged that the Construction Works will be divided into two separate contracts. The flood relief works on the river/stream/flood channels are to be managed and undertaken directly by the Office of Public Works and flood relief works on the bridges/culverts structures are to be managed by the Engineering Consultant and undertaken by a Civil Engineering Contractor. It is envisaged that, subject to the outcome of the Confirmation Process, construction works would commence in July 2020.
1.2 PROJECT OBJECTIVES, DEFINITIONS AND SCOPE
1.2.1 Project Objectives
The objectives of the Project are to:
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Stage I
Identify and map the existing and potential future3 flood hazards within the Study Area.
Assess and map the existing and potential future flood risks4 within the Study Area.
Identify viable structural and non-structural options and measures for the effective and sustainable management
of flood risk in the Gort Lowlands Area. Consideration of options and measures is to extend to the entire catchment
area of the Gort Lowlands, see Appendix M(1).
Undertake Feasibility Study.
Prepare a local FRMP (see Section 11) for the Study Area which will include for the proposed Scheme and other
measures for the area that sets out the policies, strategies, measures and actions that should be pursued by the
relevant bodies, including Local Authorities, the OPW and other Stakeholders, to achieve the most cost-effective
and sustainable management of existing and potential future flood risk within the area, taking account of
environmental plans, objectives and legislative requirements and other statutory plans and requirements. Note
CFRAM documents - Ref UoM 29.
Review proposed schemes identified in the Feasibility Study and Flood Risk Management Plan in conjunction with
the Environment Consultant during the Appropriate Assessment and Environmental Impact Assessment, identify
the preferred option and amend measures identified in the Feasibility Study as required. Prepare a Feasibility
Report which will include an Assessment of Options detailing the examination, selection and development of the
preferred option and measures.
Prepare a preliminary Benefit Cost Analysis for the preferred option.
EIAR Screening for Appropriate Assessment (This will be undertaken under a separate Contract, see Appendix E)
Undertake a Valuation Survey to identify each reputed proprietor, owner and rated or other occupier of
lands/property on which works are proposed under the preferred scheme or which may be interfered with during
the course of the works including access routes and future maintenance routes.
Stage II
Undertake a full Benefit Cost Analysis.
Bring the preferred Scheme to formal Public Exhibition, through the Arterial Drainage Acts.
Ascertain the public’s view of the proposals.
Consideration of observations received and the making of possible amendments to the Scheme.
Preparation of Exhibition Report, which will form the basis for the next stage.
Stage III
To undertake and complete the detailed design of the final preferred scheme.
To undertake the detailed design of temporary works that will be required during the construction period.
Prepare the Scheme for Confirmation by the Minister for the Department of Expenditure & Reform.
Prepare Contract Documents and undertake the procurement of a works contractor to construct the Scheme
Stage IV
Supervise the construction of the works
3 Potential future flood hazards and risk include those that might foreseeably arise (over the long-term) due to the projected effects of climate
change, future development and other long-term developments.
4 Flood risk is defined as a combination of probability and degree of flooding and the adverse consequences of flooding on human health, people and society, the environment, cultural heritage and economic activity and infrastructure
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Supervise external contract(s)
Provide ongoing detailed design ( permanent and temporary works) for both OPW and Civil Engineering Contractor
Stage V
Commissioning of the completed works
Preparation of Flood Defence Asset Report
Preparation of revised FRMP and Flood Risk Maps
Preparation of the final accounts and project report
1.2.2 Definitions
1.2.2.1 Principle Study Area – See Figure 1
Figure 1: Principle Study Area of the Gort Lowlands is Outlined in Black and Includes the Entire Catchment Area. The
Lowland Area with Predominantly Groundwater Networks consists of the Kinvarra West and Kinvarra East Lowlands.
The Consultant, in consultation with the Environmental Consultants, will be required to identify sensitive habitats or
features adjacent to, up and/or down-stream of the principal study area, which could potentially affect or be affected
by the preferred flood relief scheme option identified within the Feasibility Study.
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1.2.2.2 Areas of Potential Significant Risk
The degree of existing or potential future flood risk within the Study Area is more significant in some areas than others.
Such areas would include existing towns and villages, areas for which significant development is anticipated, and other
areas or structures for which the risk that could arise from flooding (existing or future) is understood to be significant.
These areas are defined as Areas of Potential Significant Risk (APSRs).
1.2.2.3 Flood Risk Management Plan
The Flood Risk Management Plan will set out proposed measures for the management of flood risk in the study area
(see Figure 1) and will focus on the areas where risk has been determined as being potentially significant. The Plan will
include the proposed Scheme and other measures for the area that includes the policies, strategies, measures and
actions that should be pursued by the relevant bodies, including the OPW, Local Authorities and other Stakeholders, to
achieve the most cost-effective and sustainable management of existing and potential future flood risk within the area,
taking account of environmental plans, objectives and legislative requirements and other statutory plans and
requirements (see Section 11 for details of FRMP). Note relevant sections of CFRAM documents - Ref UoM 29.
1.2.2.4 Watercourses
A watercourse is defined as any river, stream, channel, drain or flood flow route within the Study Area that conveys
flows that contribute to flooding.
1.2.3 Scope of Services
The Consultant appointed to undertake the Project shall undertake such studies, analyses, assessments, investigations
and other work as necessary to meet the Project Objectives. The services required include the following:
Stage I
(i) Project Manager Services as described at Appendix J.
(ii) Collection, analysis and timely quality assessment of data relevant to flooding within the Study Area. Note: The
members of the South Galway Flood Relief Committee have amassed detailed knowledge of issues that cover
a large proportion of the principle study area. Early and in-depth engagement with the committee will provide
the Consultant with an insight into many of the issues that will be raised throughout the project.
(iii) Establish a Project Website. Within four weeks of commencement, the consultant will develop and establish a
Project Website, and then host, maintain and update the Website until Project completion. The Website
structure shall be agreed with the client, but shall: - (a) allow users to access information including background
material, programme, newsletters etc., (b) allow users to download relevant maps and reports, and (c) allow
users to submit queries and observations and register their contact details for the dissemination of information
relating to the Project.
(iv) Identification, and condition and performance assessment, of flood defence assets and input of data into the
Flood Defence Asset Report (see Appendix N) that is to be compiled by the Consultant.
(v) Analysis of the hydrology within the study area (with the assistance of GSI)
(vi) Hydraulic analysis (including modelling) of the relevant watercourses. Note the extensive groundwater
modelling that has already been undertaken by TCD as part of an ongoing research project for an extensive
area of the lowlands (see Appendix L).
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(vii) Analysis and mapping of flood extents and hazards (e.g., depth, velocity) in relation to flooding from the
watercourses also note the requirements of Schedule C maps in Appendix H
(viii) Preliminary assessment of flood risk from groundwater and from other potential sources of flooding within the
Study Area
(ix) Determination of existing and potential future flood risks to human health, people and society, the
environment, cultural heritage and economic activity and infrastructure (the SGFRC will be able to provide
significant local information from recent flooding events).
(x) Undertake Feasibility Study and following the review with the Environmental Consultant, prepare Feasibility
Report (including Assessment of Options)
(xi) Determination and impact analysis of, and on, future spatial planning and development scenarios with regards
to flood risk, and provision of advice to the Local Authority on the consideration of flood risk in the preparation
of Development / Local Area Plans
(xii) Preparation of a FRMP (see Section 11) by determining the flood risk management objectives for the area, and
the development and appraisal of possible flood risk management policies, strategies, measures and actions to
achieve the defined objectives. Note the current wide spread public concern over the rate of run-off from the
Slieve Aughty Mountains.
(xiii) Identification of the most appropriate Scheme and set of flood risk management policies, strategies, measures
and actions, with due consideration of environmental effects, impacts up and down-stream and of potential
future changes in flood hazard and risk, see Section 10.
(xiv) Preparation of reports on the findings of the Project incorporating, where relevant, existing studies and works
(xv) Undertake a Valuation Survey (see Section 4.2) to identify each reputed proprietor, owner and rated or other
occupier of lands/property on which works are proposed under the preferred scheme or which may be
interfered with during the course of the works including access routes and future maintenance routes (see
Appendix K).
(xvi) Ensuring relevant health and safety best practices and legal requirements are adhered to, including
management of the activities of sub-consultants or third-party contractors, and assumption of the role, and
performance of the duties, of the Project Supervisor Design Process, in accordance with the Safety, Health and
Welfare at Work (Construction) Regulations 2013.
(xvii) Public and stakeholder engagement, consultation and information dissemination throughout the Project,
including attendance at public information days if required.
Stage II
(i) Project manager services as described in Appendix J.
(ii) Production of Scheme Documentation including maps, drawings, sections, schedules and Interference Notices
as described in Appendix H. (Interference Notices to formally issue through OPW).
(iii) Production of full Benefit Cost Analysis.
(iv) In advance of Exhibition, presentation of Scheme to Galway County Councillors and a separate presentation to
Senior OPW Officials.
(v) Attendance at Public Exhibition – Consultant will be required to attend at the exhibition centre(s) during the
exhibition process which will be held over a four-week period, which will necessitate attendance at the launch
and up to a further four occasions during the period to respond to queries from public and to explain details of
the scheme.
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(vi) Consideration of observations received as a result of the exhibition process, the drafting of material for
inclusion for responses to the public and the production of an Exhibition Report. It is not practicable at this
stage to pre-empt the public response or to quantify the amount or content of the observations, which might
arise from the exhibition process. This is wholly dependent on the public acceptance, or otherwise, of the
scheme proposals. It may be necessary to adapt the scheme documentation as a result of the observations
received and the final scheme proposals documented to take account of such amendments have to be
submitted for the official confirmation by the Minister of Public Expenditure and Reform as set out in the
Arterial Drainage Acts. The works specified in these finalised scheme documents form the basis of the approved
works to be undertaken by the Commissioners, with all the necessary compulsory powers associated with such
a confirmed scheme. It is hoped that the extensive consultation process proposed in Stage I will minimise
amendments at this stage.
(vii) It should be mentioned that the statutory requirements for drainage scheme documentation are onerous and
as a consequence, the preparation of documentation should undergo rigorous scrutiny and checking. The
importance of getting the documents right from the outset and the commitment in time and effort needed to
achieve this objective cannot be overemphasised.
(viii) Project Supervisor Design Process as outlined in Safety, Health and Welfare at Work (Construction) Regulations
2006-2013.
(ix) Maintenance of Project website
Stage III
(i) It may be necessary to amend the scheme proposals as a result of observations received during the exhibition
process. If this is the case, the scheme documentation must be amended to reflect these changes before being
submitted to the Minister for Public Expenditure and Reform for Official Confirmation, as set out in the Arterial
Drainage Acts.
(ii) Landowners must also be forwarded amended interference notices/letters (whichever is appropriate), advising
them of any alterations to the scheme since Public Exhibition, which might impact on their properties (to be
completed in parallel with updating of scheme documentation). Amended Interference Notices to formally
issue through OPW.
(iii) Detailed engineering design for the works, civil, structural and associated mechanical design, including all
temporary works. Liaising and cooperation with E.I.A.R. and any other consultants. All final channel routes and
works sites to be adequately surveyed when preparing final design. Note that management (see Appendix J) of
any surveys required are to be covered by the Fee.
(iv) Completion of any additional Site Investigations to enable detailed designs to be finalised. All costs associated
with the procurement and management of this work will be included in the Fee.
(v) Planning and co-ordination of works programmes in compliance with E.I.A.R requirements and constraints.
(This will involve, inter alia, developing an overall detailed plan for executing the works in phases to comply
with the E.I.A.R. and other constraints and recommending alternative phases / options to minimise disruptions
to or by the works.)
(vi) Consultation with outside parties. While a broad consultative process will be included in The Environmental
Impact Assessment the Consultant will also be required to carry out detailed consultation with certain outside
parties. It is envisaged that this will be required in the following areas;
Elected public representatives of Galway County Council
Landowners who will be affected by scheme works.
Users of the river, such as angling groups and cave divers.
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Representative groups such as SGFRC and any other relevant local representative group that might be
established during the course of the project.
Allowance to be made in the tender proposal for such consultations.
(vii) Completion of an external condition survey comprising of a comprehensive crack identification and
classification exercise with accompanying exhaustive photographic evidence on any properties located within
ten metres of any scheme works involving transport of an abnormal nature, construction, demolition or
excavation. Where a requirement for monitoring is indicated it will be included as part of the Contract. The
information gathered from this survey may be filed in a “raw” state provided that it is labelled in a fashion to
allow immediate future retrieval by a third party. If condition reports are required on any property they will be
requested by the Client. For the purposes of this exercise allow for the preparation of three (3) such reports.
Surveys are also to be carried out on all sections of public roads where access is being gained to a works site or
where works are being undertaken on / under the public road.
(viii) Project Manager Services as described at Appendix J.
(ix) Project Supervisor Design Process as outlined in Safety, Health and Welfare at Work (Construction) Regulations
2006-2013.
(x) Preparation of an Estimate of Costs for the proposed works.
(xi) Review of the cost estimate and benefit analysis for the works and agree with the Contracting Authority prior
to submission for Confirmation.
(xii) Preparation and connection together of six sets of scheme documents with such amendments, if any, that may
have been found necessary arising from the public exhibition phase for the purpose of their submission to The
Minister for the Department of Expenditure & Reform for Statutory Confirmation of the scheme. Scheme
documents are listed at Appendix H. (The Consultant should be familiar with these documents having prepared
them for the public exhibition).
(xiii) Preparation of all Contract Documents including Bill of Quantities, drawings and specifications for one or
more contracts, which will be suitable for use with the relevant Department of Finance forms of Public Works
Contract. Separate Contract Documents (standard drawings, specifications, Bill of Quantities and temporary
works design) to be prepared for all works being managed and undertaken by OPW.
(xiv) Advertisement for and evaluation of Tenders including pre-qualification procedure and recommendation of
the most economically advantageous Tender in line with public procurement policies, guidelines or
regulations in force at the time of said procurement. Preparation of separate reports on pre-qualification and
tender processes.
(xv) Update Cost Benefit Analysis Report in light of updated scheme and/or tenders received (changes should only
affect costs and ultimately the benefit/cost ratio).
(xvi) Preparation of report on tender process.
(xvii) Development of any Protocols required for the implementation of the scheme and any future maintenance
requirements.
(xviii) Maintenance of Project website
Stage IV
(i) Supervision of the external contract(s), including site supervision of works. Fees associated with site supervision will include the appointment by the Consultant of a Resident Engineer who will act, among other duties, as Employer’s Representative and an Assistant (clerk of works or junior engineer or engineering technician) whose gross salaries and expenses will be viewed as a reimbursable cost. All other costs
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associated with his/her engagement for the duration of the contract, even when such duration is greater than the Total Performance Period will form part of the Fee.
(ii) If specified in The EIAR the Consultant will engage specialist consultants e.g. Archaeologists, Biologists etc. in line with public procurement policy. GCC pay the costs of such specialists but the Consultant’s costs associated with their engagement will be included as part of the Fee.
(iii) Certification for Payment of contractor’s invoices. If invoices are in order this certification will be carried out within 14 days of receipt of invoice. If not in order the Project Co-ordinator will be notified of this in writing within said 14 days of receipt of invoice.
(iv) Provision of additional / supplementary detailed designs for permanent and temporary works by both OPW
and Civil Engineering Contractor.
(v) Project Manager Services as described at Appendix J.
(vi) Project Supervisor Design Process as outlined in Safety, Health and Welfare at Work (Construction) Regulations 2006-2013.
(vii) Maintenance of Project website
Stage V
(i) Commissioning of the completed works including the management of any testing that might be required.
(ii) Prepare revised FRMPs and Flood Risk Maps as required by current OPW CFRAM format
(iii) Preparation of the Final Account(s) and report. The project report will contain a summary of the project, the deliverables produced, a statement that all deliverables / work packages that were the subject of the contract were delivered, the schedule at which they were produced, confirmation of acceptance of the deliverables by the contracting authority, a schedule of the payments made, any deviations from the project plan or problems encountered and how they were addressed etc.
(iv) Project Manager Services as described at Appendix J.
(v) Project Supervisor Design Process as outlined in Safety, Health and Welfare at Work (Construction) Regulations 2006-2013.
1.3 PROJECT STRUCTURE AND PROGRAMME
1.3.1 Project Structure
Galway County Council (GCC) is the Lead Authority and the Contracting Authority for the purposes of the Project. The
Project will be carried out under direction and guidance from GCC, OPW, the Steering Group (see Section 2.3.2) and
other Stakeholders.
The Project shall be undertaken as a fixed sum contract by the Consultant on behalf of GCC.
The progression of this Commission is dependent on a number of factors, and all stages of the Commission may not be
required. It is a matter for GCC in consultation with OPW to decide whether this study proceeds from Stage I to Stage
II, Stage II to III, Stage III to IV and Stage IV to V. The five Stages identified above should therefore be clearly and
separately priced in the tender submissions. Note however, that the Consultant will not be requested to undertake a
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stage if they have not previously undertaken the preceding stages.
1.3.2 Project Programme
It is anticipated that the Project will commence at a date during October 2017.
Stage I
The Consultant shall submit the Draft Hydrology and Hydraulics Reports (Sections 5.8 and 6.6) and Flood Hazard Maps
(Section 6.4) within 6 months of Commencement.
The Consultant shall submit the Feasibility Report within 8 months of Commencement.
The Consultant shall submit the Draft Final Reports and associated deliverables (Section 10.9) for review by the Steering
Group within 9 months of Commencement.
The Consultant shall submit the Draft Flood Risk Management Plan and associated deliverables (Section 12.2) for review
by the Steering Group within 12 months of Commencement.
Stage II
Once approval is given to commence Stage II, the Consultant shall submit the revised scheme for review by the Steering
Group, within three months, following consultation with the Environmental Consultants.
The Consultant shall also submit all draft Scheme documentation for exhibition within three months.
The public Exhibition will take place over a four-week period and the Consultant shall produce a draft Exhibition Report,
with draft replies to all matters raised during the process, within one month.
Stage III
Once approval is given to commence Stage III, the consultant shall complete the detailed design within three months,
including any and all temporary works design required for construction.
Draft Confirmation documents, as described in Appendix I, shall be produced within one month of the completion of
detailed design.
The procurement process for a works contractor shall commence once the detailed design phase has been completed.
It is expected to run concurrently with the confirmation process.
Completion of Tender Report should occur within three months of receipt of Ministerial Confirmation for the Scheme.
Stage IV
It is anticipated that the construction phase will be completed within 18 months of signing of the works contract(s).
Stage V
It is anticipated that Stage V will be completed within 3 months of the completion of Stage IV.
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2 GENERAL REQUIREMENTS
2.1 OBJECTIVES AND SCOPE OF WORKS
The objectives of the Project and general scope of works are provided in Section 1.
2.2 REQUIRED LEVEL OF DETAIL
The Consultant shall undertake the Project to a sufficient level of detail to:
Enable GCC and OPW to proceed with confidence and robust justification with the implementation of the identified
Scheme.
Enable planning authorities to make decisions with confidence relating to the consideration of flood risk in the
preparation of development plans, local area plans and other spatial planning documents for the Principle Study
Area, and in making decisions on planning applications within the Principle Study Area, in accordance with the
Guidelines on the Planning System and Flood risk Management5.
With regards to the highland areas identified in Appendix M(1), to allow GCC and OPW to refer detailed impact
findings to relevant land owning or oversight bodies regarding land use and management, should applicable
findings be made.
The specific level of detail required for each of the various services required under this Project is set out within the
relevant Sections of the Brief.
2.3 MANAGEMENT ARRANGEMENTS
2.3.1 Project Management
GCC shall direct the Consultant in the performance of its duties, review and approve work done, and shall undertake all
other tasks normally associated with a Client. GCC shall be assisted in the performance of its duties by a Steering Group.
2.3.2 Steering Group Meetings
The Steering Group will comprise representatives of GCC, the OPW and other key stakeholders as deemed necessary.
The Consultant (Project Manager and other key staff as appropriate to the stage of the Project) shall, on appointment,
attend regular Steering Group Meetings, to be typically held every four (4) weeks.
For each Steering Group Meeting the Consultant shall prepare and submit (at least three (3) working days in advance of
each meeting) an Agenda and Progress Report (Section 2.3.3) that shall summarise progress and identify key issues,
findings, proposals and problems upon which the Steering Group may, or should, provide direction or assistance.
The Consultants shall minute the Steering Group Meetings, including a summary of actions arising with associated
responsibilities and deadlines, and submit the minutes to all Steering Group Members for review no later than three (3)
working days after the date of the meeting.
The first Steering Group Meeting shall be held within two (2) weeks of Commencement at which the Consultant shall
provide a full and detailed project programme for discussion with, and approval of, the Steering Group.
It will be the Contracting Authority’s decision as to where each meeting will be held.
5 Dept. of the Environment, Heritage and Local Government and the Office of Public Works, 2009, (www.opw.ie)
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2.3.3 Progress Reports
The Progress Reports shall outline the work undertaken during the period since the previous Steering Group Meeting,
and shall detail technical findings, proposals and any problems encountered or foreseen, with associated proposed
solutions, and provide an updated work programme for the remainder of the project for the approval of GCC, including
critical dates for delivery of information, decisions or other inputs from GCC, other members of the Steering Group or
other parties.
Each Progress Report shall be accompanied by up-to-date versions, highlighting any changes made since the previous
version, of the following documents:
Up-to-date copy of the health and safety Hazard and Risk Assessment (Section 2.5.4.2)
Inventory of Datasets (Section 3.2), that shall include all relevant data identified with a brief description, data
owners, responsibility and required date for collection, etc.
Project Programme, including a clear indication of all critical path tasks
Project Risk Assessment (a document setting out risks to the success of the Project in meeting the defined objectives
on time, along with indicators of likelihood, consequence and risk, proposed or enacted mitigation measures, and
who is responsible for managing the risk)
Register of Issues and Actions (a document setting out significant issues raised at Progress Meetings or otherwise
by GCC, Steering Group, Stakeholders or the Consultant, the actions required or enacted to address the issues,
along with required timescales / closure dates)
Updating of Project Website.
2.4 USE OF DIGITAL MEDIA AND GPS
Noting the spatial nature of much of the work involved in this Project, and the role of spatial data and GIS, the Consultant
shall be required to make extensive use of, and deliver, digital data in undertaking the Project (including spatial and
non-spatial datasets).
All spatial datasets required as Deliverables of the Project shall be delivered in an agreed format (that shall be
compatible with Mapinfo and ArcGIS) with associated metadata. The detailed metadata and interoperability
requirements of all spatial data shall be agreed with the Steering Group after commencement, but shall align with the
metadata and Interoperability for Public Authorities, as set out in articles 5 & 6 and, insofar as possible, Articles 7-10 of
the European Union Directive 2007/2/EC (the “Inspire” Directive), and other agreed international standards.
All other (non-spatial) deliverables shall be submitted in a suitable digital format such that web-based publication may
be readily achieved.
2.5 HEALTH AND SAFETY REQUIREMENTS
2.5.1 General and Legal
The Consultant shall perform any duties incumbent upon him under Health and Safety legislation.
The Consultant shall advise GCC on any matters of Health and Safety, particularly in relation to current law, which may
have implications for GCC, or require action by, or on behalf of, the OPW in connection with the Project.
A general discussion of Health & Safety issues, and the Consultant’s duties in relation to Health and Safety, will take
place during the Project Inception Meeting.
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2.5.2 Safety Statement
Consultants shall submit an up-to-date and relevant Safety Statement, compliant with Section 20 of the Safety, Health
and Welfare at Work Act, 2005, within 10 days of appointment. While the Safety Statement should cover all aspects of
work that may be encountered in the work described in this Specification, the Client reserves the right to seek Method
Statements from the Consultant concerning specific tasks where deemed necessary.
2.5.3 Appointment of PSDP
The Consultant will be appointed as, and will undertake the duties of, the Project Supervisor for the Design Process
(PSDP) for the Project under the Safety, Health and Welfare and Work (Construction Regulations) 2013, upon
Commencement. The PSDP shall fulfil all relevant obligations of the PSDP as defined in Safety, Health and Welfare and
Work (Construction Regulations) 2013 for the duration of the Project. The Consultant shall, upon Commencement,
submit to GCC written confirmation of acceptance of the appointment of the PSDP.
The Consultant corporately shall be appointed PSDP, and then appoint a competent representative as Safety
Coordinator, or a competent representative of the Consultant shall be appointed as PSDP. Tenderers must clarify in
their tenders which approach will be taken, and provide full details of the proposed competent representative to
demonstrate that they have the training and experience necessary to perform the role they will be appointed to, and
shall complete and submit with their tenders the PSDP Suitability Questionnaire (available with the tender documents).
GCC may require at any time that the Consultant provide an alternative representative to that tendered to be appointed
as PSDP, in the event that GCC deems the offered representative as unsuitable.
2.5.4 On-site activities to be undertaken by the Consultant
This section relates to survey and inspection work to be undertaken by the Consultant’s staff relating to this project.
This work will include, but not be limited to, the following:
Property Survey (Section 4.1)
Site Inspections (as required to fulfil the requirements of the Project Brief)
Flood event data collection (Section 3.3)
Any other on-site activities undertaken by the Consultant’s staff
Temporary Works Design
Should this work, or elements of this work, be undertaken by sub-consultants, the requirements of this Section will
apply to those sub-contracts.
2.5.4.1 Safety Meeting
The Consultant shall make himself available to attend a minuted safety meeting prior to any of its staff undertaking any
of the work described above. This meeting may be incorporated into the Project Inception Meeting, provided that it
occurs prior to the Consultant’s staff undertaking any of the work described above.
2.5.4.2 Hazard and Risk Assessment
A non-exhaustive Hazard and Risk Assessment for site inspections and other on-site activities is included in Appendix A.
This Assessment will provide the basis for discussion at the safety meeting as detailed in Section 2.5.4.1.
Upon appointment, and prior to the Consultant’s staff undertaking any of the work described above, the Consultant
should examine and, if deemed necessary, develop the Hazard and Risk Assessment and a copy of the completed
Assessment is to be submitted to the Client. The Consultant shall continue to actively assess and identify Hazards, Risks
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and suitable mitigation measures, throughout the duration of the Project. These are to be included in the developed
Hazard and Risk Assessment. An up-to-date copy of the Hazard and Risk Assessment shall be retained on the Project
Safety and Health File by the Consultant.
2.5.4.3 Accidents and Dangerous Occurrences
The Consultant shall immediately advise GCC verbally, and afterwards in writing of any accidents or dangerous
occurrences, loss or damage to any personnel, third parties or property arising during the execution of their duties in
relation to this project. Such accident reporting to GCC shall not relieve the Consultant of his statutory responsibilities
for accident reporting to the relevant statutory authorities and/or insurers.
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3 DATA COLLECTION
3.1 LEVEL OF DETAIL
The level of detail of the data capture and derivation to be undertaken under this Project should be sufficient to meet
the objectives of the Project and to achieve the other requirements of the Project as set out herein.
3.2 RELEVANT DATASETS
The Consultant shall search for, locate, register, extract, derive, copy (if necessary), review, quality control, format (if
necessary), interpret and make use of (as relevant) all potentially relevant information, including, but not necessarily
limited to, those referred to below:
Flood Relief / Risk Management Measures: Previous reports or studies concerning the flood hazard, risk or possible
flood relief measures, and information on current flood risk and water management measures / practices already
put in place, or other flood-related matters for the Study Area undertaken under other national programmes or
other EU Directives. Sources of such reports and information might include, but not necessarily be limited to, the
OPW, the Local Authorities, the EPA, universities, public libraries, or other sources.
Historic Flood Data: Data or information on flooding, flood extents, levels, depths, causes or mechanisms, damages,
presence of turloughs, etc. Sources of data might include, but not necessarily be limited to, Local Authorities and
the EPA. Local residents shall be contacted where particular issues or concerns arise. The Consultant shall engage
with the South Galway Flood Relief Committee and acquire all relevant and pertinent flood data arising from local
knowledge.
The OPW has collated a national web-based database of historic flood information (www.floodmaps.ie), including
press articles relating to flood events. This database is not a complete or exhaustive record of historical flood events.
The OPW will provide access to the appointed Consultants to download GIS data from this website.
Hydrometric Data: Recorded water levels and tidal data, flows, flow gaugings and ratings (stage-discharge
relationships). The majority of such data will be available from the OPW and EPA. Other sources may include, but
not necessarily be limited to, GSI, the Local Authorities, universities, the Marine Institute, Harbour Masters, and the
River Basin District Project Offices.
Meteorological Data: Rainfall, air pressure, wind speed and direction, and, if necessary, temperature and evapo-
transpiration data. Sources of data may include, but not necessarily be limited to, Met. Eireann. The recently
developed depth-duration-frequency gridded (GIS) rainfall data (Section 5.4.1) will be provided by OPW.
Land-Use Data: Data on the current and past uses of the land. Such data is likely to be available from the CORINE
dataset, available from the EPA. Other relevant data may be available from the Local Authorities or other sources.
Soil and Geological Data: Data on soil classifications, sub-soils, geology and aquifers. Sources of data may include,
but not necessarily be limited to, Teagasc and the Geological Survey of Ireland (GSI).
Planning and Development Information: Information concerning existing development, and possible future
development, would be available from plans such as the National Spatial Strategy, Development Plans (or Draft
Development Plans), Local Area Plans, Master Plans, etc.
Defence and Coastal Protection Asset Data: Information concerning the location, type, ownership, design and/or
actual performance standard and the condition of the asset. Sources of information may include, but not necessarily
be limited to, the Local Authorities, the OPW and the Department of Agriculture, Fisheries and Food.
Existing Survey / Geotechnical Data: Previously collected topographical, channel, structural or geotechnical survey
data, such as might have been collected for previous flood relief studies or other construction projects (e.g., main
drainage or sewer projects). Such data might be available from a range of sources. The OPW commissioned a LiDAR
survey and has made it available to TCD for use in their current research project which includes modelling.
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Environmental Data: Previously collected or currently available information, reports, studies, zoning and
assessments of environmental and archaeological status, issues, constraints and impacts. Sources of relevant data
may include, but not necessarily be limited to, the River Basin District Management Groups, and on the website of
the National Parks and Wildlife Service. The OPW will provide to the Consultant the public datasets, and other
datasets for which permissions are provided, that have been previously collated for the implementation of the
Water Framework Directive.
Other Receptor Data: Data on flood risk receptors, including types and locations, such as property types, utility and
transport infrastructure, national monuments and protected structures, hospitals, schools, etc. While the OPW will
endeavour to provide national datasets to the Consultant, the Consultant will be required to fill in any gaps in the
information and collect data locally.
A register of relevant reports, data and information is provided in Appendix B. This register shall however not be taken
as being a comprehensive or exhaustive list of all available and relevant reports, data and information, and further
efforts by the Consultant shall be required to locate additional reports, data and information (see academic references
in Appendix L). A full register of data collected shall be maintained by the consultant.
It is the Consultant’s responsibility to, as far as reasonably possible, identify, collect and log all relevant reports, data or
information. The Consultant shall satisfy themselves as to the quality, relevance, fitness-for-purpose and appropriate
use (or otherwise) of data promptly upon receipt of any reports, data or information.
In the event of reports, data or information being incomplete or not being of high quality or fit-for-purpose, or where
excessive delays are being incurred in securing data, GCC and other members of the Steering Group shall provide
assistance where appropriate and as reasonably possible to address any such issues to assist the Consultant. The
Consultant shall nonetheless be responsible for the collection and validation of the necessary data infilling any data gaps
where possible, and for achieving the Project objectives and requirements with the data available within the required
programme. The Consultant must provide sufficient time in the programme for data collection, quality control, etc.
Any third-party costs associated with the purchase of such data shall, subject to prior agreement, to be paid for by GCC.
3.3 FLOOD EVENT DATA COLLECTION
In the event of internal flooding of properties from rivers, turloughs, springs, swallow holes, estavelles etc. (all forms of
ground water flooding) within the Study Area during the duration of the Project, the Consultant shall, in a safe manner,
record and collect flood data such as, but not limited to, flood extents, levels, probabilities, dates and durations,
mechanisms, properties and infrastructure affected, number of evacuees, etc., and report on the flood event within
two (2) weeks of the flood.
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4 SURVEYS
4.1 PROPERTY SURVEY
4.1.1 Data Requirements and Availability
This data type includes information on property location, type, use, floor area (commercial properties only), etc. of all
properties potentially at risk from flooding as necessary for the damage/benefit analysis required to meet the project
objectives. GCC will provide available preliminary data from recent flooding events. The SGFRC has an extensive
knowledge of properties that were flooded or effected (septic tanks / access) during the flooding events of 2009 and
2015.
The OPW shall provide the Consultant, through GCC with a licensed copy of the An Post GeoDirectory that is a geo-
referenced postal database, which defines the location and classification of properties. A limited number of properties
are not registered in the GeoDirectory, and a small number (approximately 10% nationally) are not classified.
4.1.2 Consultant Duties
The Consultant shall, having regard to the data already available, identify all properties potentially at risk from flooding
in the Principle Study Area and from any other sources of flooding, and shall collect, quality control and register relevant
data, as set out above, related to these properties as necessary to meet the objectives of this project, and in particular
the flood risk assessment (Section 7).
The Consultant shall undertake surveys of the threshold levels for all properties at risk of flooding, and also for entry
points to any basements or underground car-parks. The consultant shall carry out quality assurance checks on all
property flooding information upon receipt and flag any potential problems associated with the data to the client within
two weeks of receipt.
The Consultant shall, for the purposes of the flood damage estimation, derive the floor areas of residential and non-
residential properties, from OSI maps, from ortho-rectified aerial photography or by some other method subject to
approval of GCC & OPW.
The Consultant shall identify the classification (type) of any properties that are unclassified in the GeoDirectory within
the Principle study area and identify any unregistered properties within the Principle Study Area.
The Consultant shall carry out an on-site property classification survey for all properties potentially at risk from flooding
within the Principle Study Area to determine their classification in accordance with the damage assessment methods
(Appendix D).
The Health and Safety requirements associated with this work are set out in Section 2.5.
4.2 VALUATION SURVEY
The Office of Public Works (OPW), under the Arterial Drainage Act 1945 and the Arterial Drainage (Amendment) Act
1995 is tasked with establishing ownership of all properties on which works are proposed under the preferred scheme,
including access and future maintenance routes. The Consultant is required to undertake this title research on behalf of
the OPW as part of the Project. The following are the key tasks;
The Consultants shall be provided with OSI maps/drawings, if not already available to them, showing the area for
which property ownership needs to be established.
The Consultants are expected to research and prepare proof of title as appropriate to each property. Arterial
Drainage Act 1945, Part II, Section 6 refers.
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The Consultants will be expected to prepare a report providing details, including names and addresses, of the
registered owners, rated occupiers, occupiers and/or beneficiaries of a right of way, fishing right or other similar
right for individual properties located in the area of the preferred scheme works. These details will be required on
both a spreadsheet and on associated OS maps, both of which will be required in hard and electronic copy. The
Exhibition process will require plot specific landownership maps to be printed to issue with Interference Notices.
The Consultant will also provide drawings showing the works superimposed on these ownership maps.Any third-
party costs associated with title searches shall, subject to prior agreement, to be paid for by GCC.
4.3 CHANNEL AND STRUCTURE SURVEY
4.3.1 Data Requirements & Availability
The Consultant will be responsible for identifying any channel or structural survey requirements that are needed to
develop hydraulic models outside of the Kinvarra West modelled Lowland Area as described at Appendix M(1). The
Consultant will also identify, in conjunction with TCD, areas within the Kinvarra West modelled area where
additional survey requirements exist. The consultant will develope specifications for any surveys required (to
include repeated flow surveys). The requirements and specifications will be presented to the steering group and if
no alternative is identified, the Consultant will be responsible for procuring the surveys. All costs associated with
the procurement and management of this work will be included in the Fee.
4.3.2 Consultants’ Duties
Preliminary quality assurance checks will have been carried out prior to handover of the survey data to the
Consultant. However, immediately following receipt of the data, the Consultant shall be required to assess whether
the survey data is fit-for-purpose and compatible with the modelled scheme as proposed by the Consultant. The
Consultant shall also check the quality and format of the data in terms of readability, coverage, resolution, etc. The
Consultant shall flag any potential problems associated with the data and its use to the Client within two (2) weeks
of receipt of the data, and outline and discuss proposed solutions to overcome any such problems with GCC.
Any discrepancies that may arise in the survey data during the course of using the data for hydrological analyses,
hydraulic modelling and / or flood map development shall be checked by the Consultant, and the Consultant shall
immediately communicate to GCC any such problems identified with proposals for solutions to address such
problems.
4.4 FLOOD DEFENCE ASSET SURVEY
The Consultant shall undertake a defence asset survey of all flood defence assets within the APSR and along relevant
watercourses.
The Consultant shall include as part of this survey the identification, inspection, photographing and assessment of flood
defence assets and the entry of all relevant data into the Flood Defence Asset Report.
The detailed requirements of the defence asset condition survey that the Consultant shall undertake, and the types of
defence asset and their constituent parts that shall be included as part of the defence asset condition survey, are set
out in Appendix N. The Health and Safety requirements associated with this work are set out in Section 2.5.
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4.5 MAP INFORMATION
Ordnance Survey Ireland (OSi) datasets (including cadastral maps) will be made available to the Consultant at the scales
and formats for which the OPW holds a licence. The Consultant may avail of the OPW licences for these datasets for use
only on this Project. The OPW does not accept any responsibility for errors or omissions in any information or map data
provided to the Consultant for project planning purposes.
The DTM data and map information for which the OPW holds a licence includes:
IFSAR-based DTM Data for areas outside of the extent of the LiDAR data coverage, with a vertical RSME accuracy of 0.7m
Ortho-rectified Aerial photography (62.5cm pixel resolution)
Nationwide coverage of 1:50,000 Discovery Data and Webmap in raster format
1:5000 composite maps in raster format
1:1000, 1:2500 and 1:5000 vector maps in ‘dxf’ or ‘ntf’ format
160 x Digi-Towns – Refer to www.osi.ie for further information (NOTE: The OPW makes no guarantee that such maps will be available for the Study Area)
Digi-Cities – Refer to www.osi.ie for further information (NOTE: The OPW makes no guarantee that such maps will be available for the Study Area)
The OPW will also be able to provide access to the old OSi 6” series of maps, if needed.
The Consultant will be required to sign a licensing agreement for use of the OSi data.
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5 HYDROLOGICAL ANALYSIS BEING REVIEWED
5.1 LEVEL OF DETAIL
The hydrological analysis of the whole Study Area should be comprehensive and taken to a high level of detail, such that
no further hydrological analysis should be required after completion of the Project (other than to assess minor design
variations or update the analysis after a number of years or the occurrence of an extreme event) for GCC, the OPW or
other authorities to have justifiable confidence in the implementation of the strategy and specific measures identified
through the Project to manage the flood risk within the APSR. The hydrological analysis should place particular emphasis
on flood flow estimation for the APSR in terms of, for example, statistical flood frequency estimation and the calibration
of hydrological models.
The principal study area is divided into three distinct areas: the Kinvarra West modelled lowland area, the Kinvarra East
lowland area and the Slieve Aughty highland catchment, see Appendix M(1). GSI and TCD have already undertaken
substantial hydrological analysis of the Kinvarra West lowlands area over a thirteen year period as part of numerous
research projects, see Appendix L. The Consultant shall satisfy themselves that the level and range of analysis
undertaken to date by TCD is sufficient to meet the requirements of the project. Additional requirements and
adjustments to the current Kinvarra West model will be progressed in cooperation with GSI and TCD.
For the highland catchment area, the consultant is required to address widespread concerns regarding changes of land
use within the highlands and the impact of these changes on the lowland areas. The hydrological analysis should place
particular emphasis on flood flow estimation, surface water hydrology, land uses, rates of runoff, storage and
retardation. The level of analysis of the highland catchment will be dependent on the initial findings of the Consultant
and will be determined following consultation with the Steering Group.
5.2 REVIEW AND ANALYSIS OF HISTORIC FLOODS
The Consultant shall analyse all available previous studies and reports and the historic flood data collected (see Section
3.2) in terms of peak levels, flood extents, damage caused, flows, etc. Such data shall be utilised in the analysis described
below. The Consultant shall also rank the historic flood events in the APSR, in terms of magnitude, including those for
which only outline information is available, and estimate annual exceedance probabilities for all such events using
appropriate statistical methodologies.
The Consultant shall use the peak levels and flood extents, including anecdotal information from informed individuals,
recorded or observed during historical flood events, as references for comparison with design flood levels (developed
as per Section 5.5) and flood extents (developed as per Section 6.4) to ensure consistency between observed events
and design events, particularly with reference to the estimated annual exceedance probabilities of those events.
Note that the extreme flooding events are limited to the lowland area of the Principle Study Area, see Appendix M(3).
5.3 CATCHMENT BOUNDARIES
The Consultant shall, confirm the accuracy of the established catchment boundaries and sub-catchment boundaries for
each of the Hydrological Estimation Points (see Section 5.5.3), establish additional HEPs as required and provide details
of same to GCC in compliance with GIS and hard copy format requirements for this project. The catchment boundaries
defined for the purposes of the implementation of the Water Framework Directive will be provided to the Consultant
to facilitate, and form the basis of this process, but the Consultant shall review and confirm these boundaries and, with
the assistance of the OPW, GSI and, where relevant, through cooperation with consultants undertaking relevant CFRAM
Studies resolve any discrepancies arising.
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5.4 ANALYSIS OF HYDROMETRIC AND METEOROLOGICAL DATA
5.4.1 Rainfall Data
The Consultant shall use relevant historic and recorded rainfall data that is available from Met Eireann in terms of severe
rainfall event depths, intensities, durations, etc., and shall estimate probabilities for significant and / or recent events
in the Study Area, with reference and comparison made to the Flood Studies Update data and other relevant research.
The OPW shall provide the Consultant upon appointment with the rainfall depth-duration-frequency data as generated
by Met Eireann for the Flood Studies Update. This data, available in GIS format, provide national coverage of depth-
duration-frequency data for 2km grid squares.
5.4.2 Hydrometric Data Review
The Consultant shall familiarise themselves with the analyses of historic and recorded water levels that has already been
undertaken by GSI and TCD. The current model only includes basic tidal inputs, in terms of peak flood levels and flows.
No study has been undertaken with the current model to tidally adjusted hydrograph shape, flood volumes, etc. and
estimated probabilities for major or recent events, with reference and comparison made to the Flood Studies Report
and / or other relevant research. The Consultant shall satisfy themselves that the level and range of analysis undertaken
to date is sufficient to meet the requirements of the project. The Consultant is responsible for progressing any additional
in consultation with GSI and TCD.
Tenderers should note that annual maxima data are manually extracted rather than being derived directly from digitised
data, and that in some instances discrepancies exist between the two datasets. Where such discrepancies occur, the
annual maxima values that have been manually extracted would typically be more reliable.
5.4.3 Hydrometric Gauging Station Rating Reviews
The four existing rated gauging stations on the main contributories to the Lowland areas have been rated by the OPW
and TCD. Only preliminary rating work has been undertaken to date on the Cloonteen River, see Appendix M(4) and the
Consultant may have to procure additional flow measurements at this location. The Consultant shall familiarise
themselves with ratings that have been undertaken and the upper range of the stage-discharge relationships at all of
the hydrometric stations identified in Appendix M(4) and satisfy themselves that the information is satisfactory to meet
the requirements of the Project. The Consultant shall ensure appropriate understanding of the quality and limitations
of the flood flow data and reduce any uncertainty associated with the upper range of the ratings and of its extrapolation
beyond the maximum gauged flow over the period of record of the station. The Consultant shall satisfy themselves with
the calibration of the modelled rating to the recorded flow gaugings (as deemed reliable) up to the maximum gauged
flows and use surveyed data and supporting information (e.g., from site visits).
For the studies required in the Highland areas, the Consultant shall identify and undertake any additional detailed
localised hydraulic modelling that is required, and any associated work to meet accepted best practice, including site
visits.
Any survey requirements for the modelling of the hydrometric stations shall be provided as part of the channel and
structure survey work set out under Section 4.
5.5 ESTIMATION OF DESIGN FLOOD PARAMETERS
The Consultant shall, for all Hydrological Estimation Points (see Section 5.5.3), derive best estimate design fluvial flood
parameters including peak flows, hydrographs, flood volumes and other design flood parameters, such as downstream
boundary levels, as necessary to deliver the requirements of the Project.
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5.5.1 Design Event Probabilities
The range of probabilities for which the Consultant shall derive design flood parameters as set out herein shall include
those with an annual exceedance probability (AEP) of 50%, 20%, 10%, 5%, 2%, 1%, 0.5% and 0.1%. The Consultant will
liaise with the GSI when determining the appropriate parameters to be considered when developing AEPs.
5.5.2 Design Event Flow Estimation Methods
The Consultant shall estimate design flood flows and required event durations using a range of methodologies as
appropriate to the catchments, ground water network and data availability, including, but not necessarily limited to:
Rainfall-Runoff, Runoff-Routing or catchment modelling, as would be necessary for event simulation,
methods for estimating index design flood flows and growth curves using, the Flood Studies Update methodologies,
or the Flood Studies Report and other relevant research if it is agreed by the OPW that the Flood Studies Update
methodologies are not appropriate
the full use, and statistical analysis, of historic gauged levels and flows, including those where records might exist
but for which there may be no gauged data.
5.5.3 Hydrological Estimation Points
The Consultant, in conjunction with GSI and TCD, shall derive best estimate design fluvial flood parameters based on
the methods referred to above at Hydrological Estimation Points. The existing Hydrological Estimation Points are
identified in Appendix M(4). The Consultant will identify and establish additional HEPs as required for the project.
5.5.4 Hydrological Calibration and Validation
The Consultant shall validate the estimates of the design flood parameters (other than extreme peak sea levels) to
recorded data as far as reasonably possible, based on historic or recorded flood event data.
5.5.5 Sensitivity Tests
The Consultant shall undertake sensitivity tests as appropriate to determine degrees of uncertainty associated with the
design flood event parameters.
5.6 FUTURE ENVIRONMENTAL AND CATCHMENT CHANGES
The Consultant shall estimate design flood parameters with appropriate allowances for possible future changes, such
as future development, land use changes and climate change, in accordance with the requirements set out in Appendix
C.
The relevant allowances to be adopted and used for each of the two possible future scenarios (the MRFS and the HEFS)
that shall be assessed by the Consultant shall be agreed in consultation with the Steering Group.
5.7 HYDRO-GEOMORPHOLOGICAL ASSESSMENT
The Consultant shall undertake, based on available or readily derivable information, a preliminary assessment of the
hydro-geomorphology and sediment transport issues of the relevant watercourses, in so far as they may affect flood
risk within the Study Area.
The assessment should include, but not necessarily be limited to, any available information, historical records or
evidence on erosion or deposition (e.g., such as might be available from the relevant Water Framework Directive River
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Basin District project), an analysis of the topography, sub-surface materials (soil, sub-soil, geology, etc.), and, where
necessary, site visits.
Based on the assessment set out above and the risk indicators defined in Section 7, the Consultant shall assess and
report on the existing and potential risk associated with the hydro-geomorphology in the Study Area, and how the
hydro-geomorphological conditions might affect flood risk.
5.8 HYDROLOGY REPORT
The Consultant shall submit to GCC detailed, technical Draft Hydrology Reports that shall set out the work and analysis
undertaken in relation to, and the findings and conclusions of, the hydrological analysis as defined within Section 5,
accompanied with all hydrometric and meteorological data used and created. The typical structure and contents of the
Draft and Final Hydrology Reports shall be agreed by the Steering Group, subject to approval of the GCC.
GCC, assisted by the Steering Group and other experts as deemed necessary by GCC, shall review the Draft Hydrology
Report and submit observations to the Consultant within three (3) weeks of receipt.
The Consultant shall review the observations submitted by GCC, and prepare and submit to GCC Final Hydrology Report
that suitably addresses the observations of GCC within two (2) weeks of receipt of the observations from GCC.
In the event that the GCC does not consider that all observations have been appropriately addressed, GCC shall submit
further observations to the Consultant to be addressed by the Consultant as set out above. Once GCC is satisfied that
all observations have been appropriately addressed, the Consultant shall re-submit the Final Hydrology Report.
The Consultant shall submit four (4) hard copies of the Final Hydrology Report.
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6 HYDRAULIC ANALYSIS
6.1 LEVEL OF DETAIL
The level of detail of the hydraulic analysis to be undertaken under this Project should be sufficient to enable the
Consultant to fully meet the requirements and objectives of the flood mapping, flood risk assessment, development
and appraisal of the Scheme and other flood risk management actions and measures (and associated assessments) and
the preparation of a Flood Risk Management Plan, as set out herein.
Within the APSRs, the hydraulic analysis should be comprehensive and taken to a high level of detail, such that no
further hydraulic analysis should be required to progress the Scheme and other measures (other than to assess minor
design variations or for validation and / or re-calibration after the occurrence of an extreme event) to manage the flood
risk within the area.
The Consultant is to satisfy themselves that the level of detail developed by TCD for the Kinvarra West lowlands is
sufficient to meet the requirements of the project. Within other areas of the lowlands the Consultant will be required
to carry out hydraulic analyses which should be the best achievable within the constraints of the survey specification
and available data to enable reasonable estimates of flood hazard and risk.
The Consultant will identify appropriate areas within the highlands and undertake hydraulic analyses as required to fully
meet the requirements and objectives of the Project. The analyses should be the best achievable within the constraints
of the survey specification and available data to enable a comprehensive report on the highland catchment.
6.2 DEVELOPMENT OF FLUVIAL HYDRAULIC MODELS
6.2.1 Fluvial Model Development
Where required, the Consultant shall develop dynamic hydraulic models and their associated floodplains, to analyse
historic flood events and estimate design and potential future flood levels, depths, velocities and extents. For the
Kinvarra West lowlands, this will be progressed through the developing TCD model, developed as part of an ongoing
research project.
The Consultant shall develop models to the required level of detail for the relevant watercourses, making full and best
use of the survey, calibration and other information captured, provided or developed as specified herein.
The Consultant shall undertake the modelling of in-bank fluvial reaches using 1-dimensional modelling schematised in
accordance with best practice to appropriately model conveyance routes, storage and attenuation and other hydraulic
features. The Consultant shall undertake the out-of-bank (floodplain) modelling using 2-dimensional modelling or other
types of modelling capable of accurately simulating the 2-dimensional propagation of flow, dynamically linked to 1-
dimensional in-bank models.
The hydraulic models shall be developed using one of the following modelling software packages:
ISIS / ISIS-2D / Tuflow
Mike 11, Mike 21, Mike Flood
Hydraulic modelling software packages other than those listed above may not be used in undertaking the Project.
6.2.2 Fluvial Model Calibration
The Consultant shall ensure that the flood flows within the hydraulic models are calibrated to the flood flow estimates
at the Hydrological Estimation Points to ensure hydrological continuity (taking account of flood attenuation explicitly
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simulated within the hydraulic modelling) and that the design flood flows for each AEP are maintained along all lengths
of relevant watercourses. Such adjustment might, for example, be by the provision of appropriate lateral inflows and
ensuring appropriate inflow from tributaries, or by running the hydraulic models for individual reaches.
The Consultant shall calibrate and verify the fluvial hydraulic models against a number of suitable past flood events (not
less than four (4) events for each APSR if relevant data is available). The calibration and verification of the models shall
make use of the best available data including, but not limited to, hydrometric data, photographs, videos, press articles
and anecdotal information provided by local authority staff and other Stakeholders. The models should be verified to
vertical accuracies of not less than 0.2m for out-of-bank and 0.4m for in-bank flows, subject to the availability of suitable
calibration data.
6.2.3 Fluvial Model Design Runs
The Consultant shall run the dynamic hydraulic models for design flood events to determine flood levels, extents and
other parameters as necessary for the Consultant to produce the required flood maps (see Sections 6.4 and 7.3), and to
assist in the robust development and appraisal of potential flood risk management methods, options measures and
potential strategies. For the Kinvarra West lowlands model, collaboration will be required with TCD.
The Consultant shall run the models for design events of the full range of probabilities specified in Section 5.5.1 for
existing conditions and for the MRFS, and for the 10%, 1% and 0.1% AEP design flood events for the HEFS.
6.3 SENSITIVITY TESTS
The Consultant shall undertake sensitivity tests for each and all forms of modelling as described above as appropriate
to determine the robustness and sensitivity of the models and the design flood levels, extents, etc. estimated using the
models. Such tests should include, but not necessarily be limited to, variations in roughness parameters, flow values,
boundary conditions and (within APSR) afflux parameters at hydraulically-significant structures.
6.4 FLOOD HAZARD MAPPING
6.4.1 Level of Detail
The Consultant shall produce flood hazard maps for the APSR to the best accuracy and level of detail that can be
achieved with the methodologies specified and the available data. The flood hazard maps should provide the
information necessary for spatial planning (e.g., for Development Plans and Local Area Plans) and the – ref assessment
of planning applications, as well as for the flood risk assessment, development and appraisal of flood risk management
actions and measures (and associated assessments) and the preparation of a Scheme, as set out herein.
The flood hazard maps produced for the areas at risk of flooding from the relevant watercourses should be of sufficient
detail and reliability (subject to the availability of calibration data) to provide the information necessary for preliminary
flood risk assessments (e.g., Stage II FRA as set out in the Guidelines on the Planning System and Flood Risk Management
– DoEHLG & OPW, November 2009) to be made in relation to spatial planning and planning applications. It is not
however anticipated that the maps produced for the areas at risk of flooding from the relevant watercourses would be
adequate for final decisions relating to major development proposals, or those subject to appeal, and that such
proposals may require further flood risk analysis (by the planning permission applicant and / or planning authority)
beyond that delivered under this Project.
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6.4.2 Flood Mapping Requirements
Based on the modelling and analysis described herein, and making full and best use of the survey and other information
captured, provided or developed as specified herein, the Consultant shall produce a range of flood hazard maps, as set
out below. The range of flood maps the Consultant shall produce shall include:
1. Flood Extent Maps, which shall show the extents of flooding, and include the following:
i) An indicator of degree of confidence (see Section 6.4.3) associated with the flood extent
ii) Tables of peak flood flows for all modelled design flood event probabilities at each of the Hydrological
Estimation Points (see Section 5.5.3). The flows presented shall be the total flows in the full valley section at
each Point, rather than just those that are in-channel or attached to an individual model node.
iii) Tables of peak flood levels for all modelled design flood event probabilities at:
i) all nodes (sited at cross-section locations or model nodes, and to be named according to an agreed naming
convention) along the centre line of the main channels and other flow paths modelled using 1-dimensional
fluvial hydraulic models (and within APSR modelled using other techniques)
ii) points within modelled domains of coastal flooding as appropriate to the nature of the model and to meet
the needs potential users of the flood hazard maps (such points would typically be at not more than 500m
centres)
iv) Areas benefiting from flood protection from flood defences with the associated standard of protection and the
location and extent of the flood defence assets
2. Flood Zone Maps, which shall show only three flood extents, as flood zones A, B and C, to facilitate implementation of the Guidelines on the Planning System and Flood Risk Management.
3. Flood Depth Maps, which shall show the depths of flooding, in ranges / classifications to be confirmed by the OPW.
4. Flood Velocity Maps, which shall show the velocities of floodplain flow, in ranges / classifications to be confirmed by the OPW.
5. Flood Hazard Function Maps, which shall show a function of flood hazard (the ‘risk to life’) calculated from depth and velocity and, if relevant, a debris factor. The function to be used shall be confirmed by the OPW.
The Consultant shall produce each of the above maps for each of the scenarios (current, MRFS and HEFS) for the flood
event probabilities set out in Table 6.1 below.
On completion of the Scheme, the Consultant is to revise the FRMP and Flood Risk Maps as required by current OPW
CFRAMs.
The terms ‘GIS’ and ‘Print-Ready’ as used to describe the types of map within Table 6.1 refer to mapping formats as
described in Section 6.4.4.
Flood Velocity (item 4 above) and Hazard Function Maps (item 5 above) are only required for APSR.
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Type of Flood Map Flood Event Probabilities to be Mapped for Each Scenario
Current MRFS HEFS
Flood Extent – GIS All Probabilities All Probabilities 10%, 1%, 0.1%
Flood Extent – Print-Ready 10%, 1%, 0.1% 10%, 1%, 0.1% Not Required
Flood Zone – GIS 1%, 0.1% 1%, 0.1% Not Required
Flood Zone – Print-Ready 1%, 0.1% Not Required Not Required
Flood Depth – GIS All Probabilities 10%, 1%, 0.1% Not Required
Flood Depth – Print-Ready 10%, 1%, 0.1% Not Required Not Required
Flood Velocity – GIS All Probabilities Not Required Not Required
Flood Velocity – Print-Ready 10%, 1%, 0.1% Not Required Not Required
Flood Hazard Function – GIS 10%, 1%, 0.1% Not Required Not Required
Flood Hazard Function – Print-Ready 10%, 1%, 0.1% Not Required Not Required
Figure 6.1; Flood Mapping Requirements
The ‘Print-Ready’ Flood Extent and Flood Zone maps shall include all of the flood event probability extents on the same
map. For all other ‘Print-Ready’ maps, the Consultant shall prepare separate maps for each flood event probability.
The Consultant shall post-process the outputs of the hydraulic models before production of the flood maps to, for
example, eliminate small islands and pools and remove flooded areas with no hydraulic connectivity to the source of
flooding.
6.4.3 Degrees of Confidence
The Consultant shall, for the purposes of the Flood Extent Maps, derive an indicator of the degree of confidence in the
estimated flows and levels and consequently in the mapped flood extents.
The indicator of degree of confidence shall be based on some or all of the following factors:
Hydrological:
Design flood parameter estimation method(s)
Availability, proximity and quality of recorded flood flow or tidal level data
Probability of the design flood event
Hydraulics:
The quality (including cross-section spacing) of the survey data
Method for estimating roughness
Complexity of the relevant hydraulics and / or hydraulic model
Availability, proximity and quality of flood level or extent calibration data and / or the outcomes of the
calibration and validation
Topographical (Flood Extents)
The quality of the floodplain survey data
The local topography / slope of the floodplains
The detailed methods to be used for determining the degree of confidence in flows, levels and extents shall be agreed
by the Steering Group, subject to approval of GCC.
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The uncertainties (or degree of confidence) in the flood extents to be represented on the flood extent maps shall be
based on the uncertainties in the flood levels, and a categorisation of the projected spatial range of the possible flood
extents based on this uncertainty in level, taking into account the local topography. The method to derive extent
uncertainty based on uncertainties in levels shall follow the method set out in Appendix G. Software code for the
application of this method has been developed and can be made available to the Consultant if so required, but this code
would require adaptation / amendment to produce the required outcomes dependent on the modelling and mapping
software being used, and should not be relied upon as ready-to-use.
The Consultant shall present the degrees of confidence for each mapped flood extent by means of varying flood extent
boundary line types for the flood extents.
Additional hydraulic model runs will not be required as part of the assessment of degree of confidence, although the
determination of degree of confidence in level and extent will require analysis based on model outputs, and may be
automated within a modelling process.
6.4.4 Formats for Delivery of Flood Hazard Maps
The Consultant shall deliver the maps in digital format in two formats:
GIS Format: Maps to be provided as layers, tables, meta-data and / or files (as appropriate) in a GIS format
compatible for direct import into MapInfo and ArcGIS.
Print-Ready Format: Maps to be provided in an editable (e.g., AutoCAD dxf) and pdf format that will provide for
direct printing (i.e., without merging, amendment, or other manipulation) to hardcopy at A3 size, such that the
printed image is in a standard map / drawing format, including borders, title block with location map, legend, notes,
map title / origin, etc.
The Consultant shall provide all of the flood flows and levels (Section 6.4.2) as attribute tables within the GIS Format
version of the flood extent maps, including those for the full range of AEP flood events, for all scenarios, and for all
Hydrological Estimation Points and model nodes respectively. Limited tables of flood flows and levels (i.e., for only a
selection of flood event AEPs) shall be reproduced on the print-ready format maps.
The Consultant shall provide the Print-Ready Format version of the maps to a printed scale at A3 paper size of 1:5 000
and 1:25 000 for APSR, overlain on appropriately-scaled OSi cadastral base-maps.
The details of GIS data and ‘Print-Ready’ formats for the flood maps (colour palettes and other details of presentation)
shall be agreed by the Steering Group, subject to approval of GCC.
6.5 OPTION EVALUATION
The Consultant shall specify and acquire simulations and model runs as necessary to develop and appraise options for
possible flood risk management actions and measures (see Section 10).
6.6 HYDRAULIC REPORT
The Consultant shall submit to GCC a detailed, technical Hydraulics Report that shall set out the work and analysis
undertaken in relation to, and the findings and conclusions of, the surveys as defined within Section 6 and the hydraulic
analysis as defined within Section 6.1, 6.2 and 6.3.
The Consultant shall supply the following as part of, or as an accompaniment to, the Draft and Final Hydraulics Report:
All survey data, including digital data files, as detailed in Section 6.
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Digital hydraulic model files, including, but not necessarily limited to, calibration, verification, design run and
sensitivity analysis model and results files, for the work detailed in Section 6, excluding Section 6.5.
A copy of the defence asset database with all flood defence asset geometric and condition survey completed and
accurately entered, including the defence asset survey deliverables, as detailed in Section 4.1.
GCC, assisted by the Steering Group and other experts as deemed necessary by GCC, shall review the Draft Hydraulics
Report and submit observations to the Consultant within three (3) weeks of receipt. The Consultant shall review the
observations submitted by GCC, and prepare and submit to GCC a Final Hydraulics Report that suitably addresses the
observations of GCC within two (2) weeks of receipt of the observations from GCC.
In the event that GCC does not consider that all observations have been appropriately addressed, GCC shall submit
further observations to the Consultant to be addressed by the Consultant as set out above. In the event that GCC is
satisfied that all observations have been appropriately addressed, the Consultant shall re-submit the Final Hydraulics
Report.
The Consultant shall submit four (4) hard copies of the Final Hydraulics Report.
6.7 FLOOD MAPPING REPORT
The Consultant shall submit to GCC a detailed, technical Flood Mapping Report that shall set out the work and analysis
undertaken as defined in Section 6.4.
The Consultant shall supply as part of, or as an accompaniment to, the Draft and Final Flood Mapping Report digital
copies of the GIS-Format and Print-Ready Format Flood hazard maps, as detailed in Section 6.4.
GCC, assisted by the Steering Group and other experts as deemed necessary by GCC, shall review the Draft Flood
Mapping Report and submit observations to the Consultant within three (3) weeks of receipt. The Consultant shall
review the observations submitted by GCC, and prepare and submit to GCC a Draft Final Flood Mapping Report that
suitably addresses the observations of GCC. The Draft Final Flood Mapping Report may be submitted with the Draft Final
Report.
GCC, assisted by the Steering Group and other experts as deemed necessary by GCC, shall, within two (2) weeks of
receipt, review the Draft Final Flood Mapping Report to ensure that all observations have been appropriately addressed.
In the event that GCC does not consider that all observations have been appropriately addressed, GCC shall submit
further observations to the Consultant to be addressed by the Consultant as set out above. In the event that GCC is
satisfied that all observations have been appropriately addressed, the Consultant shall re-submit the Draft Final Flood
Mapping Report as the Final Flood Mapping Report.
Note that the Flood Mapping Report must also contain the revised FRMP and Flood Risk Maps that the Consultant is
to prepare on completion of the scheme. The maps are to comply with current OPW CFRAMs requirements, see
Section 6.4.
The Consultant shall submit four (4) hard copies of the Final Flood Mapping Report, and accompanying deliverables
including the flood maps.
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7 FLOOD RISK ASSESSMENT
7.1 FLOOD RISK RECEPTOR GROUPS
The Consultant shall assess and map the potential adverse consequences (risk) associated with flooding in the APSR, to
four risk receptor groups, namely:
Society (including risk to people),
The Environment,
Cultural Heritage,
The Economy,
Requirements for these assessments are set out below. The Consultant shall undertake the risk assessments using
relevant information for all of the design flood event probabilities referred to in Section 6.2.3 for existing conditions and
for the MRFS. The Consultant shall derive indicative estimates of risk for the HEFS based on flood damages as derived
for the MRFS scaled using only the HEFS flood events with an AEP of 10%, 1% (0.5% for coastal flooding) and 0.1%.
7.1.1 Social Risk
The social flood risk shall be assessed, mapped and reported upon using four methods and indicator sets:
i) the location and number of residential properties
ii) the location, type, an indicator of vulnerability and number of potentially high-vulnerability sites, such as residential homes for children, the elderly or disabled, etc.
iii) the location, type, an indicator of vulnerability and number of valuable social infrastructural assets, such as fire stations, Garda stations, ambulance stations, hospitals, government and council buildings, etc.
iv) the location, type, an indicator of vulnerability and number of social amenity sites, such as parks, leisure facilities, etc.
7.1.2 Risk to the Environment
The flood risk to the environment shall be assessed and mapped and reported upon using three methods and indicator
sets:
i) The location, type, an indicator of vulnerability and number of installations referred to in Annex I to EU Directive 96/61/EC (1996) concerning integrated pollution prevention and control and other significant potential sources of pollution. (NOTE: Information on IPPC Licenses are available on the Environmental Protection Agency Website (www.epa.ie) and information on Section 4 and Section 16 licenses under the Water Pollution Act are available from the Water Pollution Control Section of the relevant Local Authorities)
ii) The location, extent, nature and an indicator of vulnerability of areas identified in Annex IV(1)(i), (iii) and (v) to the Water Framework Directive (EU Directive 2000/60/EC)
iii) The nature, location, an indicator of vulnerability and areas of other environmentally-valuable sites, such as SACs
7.1.3 Risk to Cultural Heritage
The flood risk to cultural heritage shall be assessed and mapped and reported upon using one method and indicator
set:
i) The location, type, an indicator of vulnerability and number of sites or assets of cultural value
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7.1.4 Risk to the Economy
The flood risk to the economy shall be assessed and mapped and reported upon using four methods and indicator sets:
i) The location, type (residential and classifications of non-residential) and numbers of properties, with associated frequency-depth-damage information based on property type
ii) The density of economic risk expressed as annual average damage (euro/year) per unit area (e.g., per 100m or
500m square)
iii) The location, type, an indicator of vulnerability and number (and / or lengths) of transport infrastructural assets, such as airports, ports, motorways, national and regional roads, rail, etc.
iv) The location, type, an indicator of vulnerability and number of utility infrastructural assets, such as electricity
generation and sub-stations, water supply and treatment works, natural gas and oil facilities, important telecom interchanges, data repositories, etc.
The Consultant shall assess and calculate the economic damages and risk for risk indicators (i) and (ii) above using the
methodology based on that set out in Appendix D, subject to approval of GCC.
As noted in Section 4.1, the Consultant shall for the purposes of the economic risk estimation for properties, use the
surveyed floor / threshold levels.
7.1.5 Indicators of Vulnerability
The OPW shall provide the Consultant with the indicators of vulnerability for each type of social, environmental, cultural
and economic risk receptor, where noted above, and excluding economic risks (i) and (ii) that shall be calculated using
the methodology as set out in Appendix D. The indicators of vulnerability shall typically be a categorisation of
vulnerability (e.g., very high to very low) or, where possible, as a numerical or economic consequence or depth-
consequence curve in the event of flooding.
The definition of the indicators of vulnerability shall be reviewed and, if necessary and agreed, refinement of the
Steering Group, subject to approval of GCC.
7.2 REPORTING OF FLOOD RISK INDICATORS
The results of the flood risk assessments under the four risk receptor groups referred to under Section 7.1 shall be
described in the Draft Final Report (Section 10.9).
7.3 FLOOD RISK MAPS
The Consultant shall, for the APSR, prepare flood risk maps that present in a clear manner the flood risk as defined under
Section 7.1. The Consultant shall prepare a number of sets of maps as set out below.
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7.3.1 Specific Flood Risk Maps
7.3.1.1 Indicative Number of Inhabitants
For the social risk indicator i) [Section 7.1.1, i)], the Consultant shall prepare an individual set of maps presenting the
indicative number of inhabitants at risk of flooding within each of the flood events with AEPs of 10%, 1% and 0.1% by
means of a population density (i.e., number per unit area) or total (i.e., number within a given area, such as an APSR or
a discrete flood cell within an APSR).
The indicative number of inhabitants shall be derived from the number of residential properties, supplemented by
secondary data, where available, (such as the typical numbers of residents per property in the relevant area or sub-
area). The method for defining the indicative number of inhabitants shall be reviewed and refined by the Steering Group,
subject to approval of GCC.
The Consultant shall prepare these maps in GIS-Format and in Print-Ready Format (See Section 6.4.4) but only for the
APSR for the current scenario, and in GIS-Format only for the MRFS (but not for the HEFS). The numbers of inhabitants
as represented on the maps shall also be provided as attribute data to the maps.
7.3.1.2 Types of Economic Activity
For the economic risk indicator i) [Section 7.1.4, i)], the Consultant shall prepare an individual set of maps presenting
the types of property use for areas within the APSR according to certain categories, or the category of an IRR,
representing the type of economic activity at risk from flooding from a flood event with an AEP of 10%, 1% and 0.1%.
The definition of the categories of economic activity shall be provided by the OPW, but shall be reviewed and refined
by the Steering Group, subject to approval of GCC.
The Consultant shall prepare these maps in GIS-Format and in Print-Ready Format (See Section 6.4.4) but only for the
APSR for the current scenario, and in GIS-Format only for the MRFS (but not for the HEFS). The categories of economic
activity as represented on the maps shall also be provided as attribute data to the maps.
7.3.1.3 Economic Risk Density
For the economic risk indicator ii) [Section 7.1.4, ii)], the Consultant shall prepare an individual set of maps presenting
the annual average damage.
These maps need only be prepared in GIS-Format (i.e., not in Print-Ready Format – See Section 6.4.4) for the APSR and
for the current scenario and MRFS (i.e., not for HEFS). The economic risk density as represented on the maps shall also
be provided as attribute data to the maps.
7.3.1.4 General Flood Risk Maps
For all risk indicators other than those for which specific flood risk maps are to be prepared (Section 7.3.1), the
Consultant shall prepare, on a separate set of maps for each risk receptor group (i.e., Social, the Environment, Cultural
Heritage and the Economic risk), maps with all of the risk indicators for that group overlain on the Flood Extent Maps
(but excluding all of the requirements of sub-points 1.a) to 1.d) of Section 6.4.2) including extents for flood events with
AEPs of 10%, 1% and 0.1% (i.e., with all flood event probabilities on a single set of maps).
The Consultant shall prepare sets of risk maps in both GIS and ‘Print-Ready’ formats (see Section 6.4.4) as set out above
for both the APSR for the current scenario, and in GIS-Format only for the MRFS (but not for the HEFS).
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The Consultant shall geo-reference the IRRs, where such data is not already geo-referenced, and shall provide as
attribute tables attached to each IRR within the GIS Format version of the flood risk maps the category, type, nature,
vulnerability, flood likelihoods and depths and other relevant data for each IRR.
The details of the GIS and ‘Print-Ready’ formats for the flood maps (appropriate symbols, colour palettes and other
details of presentation) shall be agreed by the Steering Group, subject to approval of GCC.
7.4 FLOOD RISK MANAGEMENT OBJECTIVES
Generic flood risk management objectives, linked to the risk receptor indicators and with associated Global Weightings,
shall be provided to the Consultant by the OPW after Commencement
Based on the outcomes of the flood risk assessment outlined herein, the Consultant shall for each Unit of Management,
sub-catchments within each Unit of Management, each APSR and each IRR assess the relative importance of each
objective within the relevant area or for the relevant receptor. The Consultant shall then assign an appropriate Local
Weighting for each objective that will subsequently be used in developing and appraising flood risk management options
(see Section 10).
To promote national consistency in assigning the Local Weighting, the Consultant shall follow guidelines to be provided
by the OPW, but which shall be reviewed and refined by the Steering Group, subject to approval of GCC. These guidelines
shall expand on the following, providing rules and / or examples with respect to each objective:
Local Weighting Description of Importance
Very High National or International Importance
High Regional Importance
Moderate Significant Local Importance
Low Moderate Local Importance
Very Low Negligible or Minor Local Importance
N/A Objective Not Relevant within Area or for Individual Risk Receptor
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8 ENVIRONMENTAL ASSESSMENT
8.1 ENVIRONMENTAL IMPACT ASSESSMENT
A consultant will also be appointed to undertake an Environmental Impact Assessment Report (EIAR) for the Project.
The Consultant shall provide such information as necessary to the EIAR consultant, and shall liaise with that consultant
as necessary to permit that consultant to perform their duties and shall ensure that any findings or outcomes of the
EIAR are taken into account as appropriate in undertaking the Project.
The Main Consultant (at least three lead team members) shall attend at all Public Information Days.
The technical specification for the EIAR is illustrated in Appendix E.
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9 CONSULTATION AND ENGAGEMENT
The Consultant shall undertake stakeholder and public consultation activities as necessary to promote and provide for
the awareness and active engagement of the public and all stakeholders that might have an interest in, or be affected
by the Scheme (and the decisions made towards the development of the Scheme), to ensure that the public and
stakeholders have the opportunity to review and make comments and submissions and participate in the decision
making processes, as appropriate.
The Consultant shall assist the environmental consultant with the preparation for a Public Consultation Day to present
and receive comment on the preferred Scheme. This assistance shall include the preparation and provision of
information, drawings and other material by the Consultant as necessary.
The Consultant shall provide not less than two appropriately senior staff, including the project manager, who have been
closely involved with the Project to attend the Public Consultation Day and respond to questions arising from the public
and stakeholders. The Consultant shall also present the preferred Scheme to Councillors (which may be immediately in
advance of the opening of the Public Consultation Day to the public).
The Consultant shall receive and register relevant details of all queries related to the Project; either by email, post, via
the website or by other means. The Consultant shall prepare and issue appropriate responses to all queries, other than
those received from the media or politicians for which the Consultant shall prepare an appropriate draft response and
forward same to GCC for review and issue. All responses shall also be added to the register of queries. The Consultant
shall meet with interested parties as necessary, which may include meetings outside of normal office hours.
In undertaking such consultation and engagement activities, the Consultant shall be required to perform the services
set out in Appendix F.
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10 DEVELOPMENT OF FLOOD RISK MANAGEMENT OPTIONS
10.1 LEVEL OF DETAIL
The analysis, and method and option development and appraisal, to derive the preferred Scheme and set of other
actions and measures, as described herein, should form a robust and sound foundation for the Scheme and other
measures to be taken to public exhibition or planning (as appropriate) and subsequent implementation. The
identification of the preferred Scheme and other measures and the rejection of any method or option shall be robust
and with clear and transparent reasoning.
The Consultant shall develop, appraise and report on the Scheme and other measures to the degree of detail typically
associated with a feasibility study. This shall include, but not necessarily be limited to, the following:
A detailed plan, layout, sections and profiles, as appropriate, of any proposed works, including any proposed land
take
The anticipated post works flood profile
The size and location of channel(s) required with the accompanying quantities and types, if any, of materials to be
excavated
The height, levels, geometry and volumes of any structures to be constructed
The source of suitable material to construct embankments or other structures (with preference to sites within the
Study Area), and locations for any necessary waste / soil disposal (with volumes)
Details as to how any surface water discharging to the channels within the Principle study area is to be managed,
including volumes of water, if any, to be stored or pumped
The required maintenance regime for the Scheme and other measures
10.2 PREFERRED DESIGN STANDARDS
The preferred design standards (i.e., flood event probabilities that the Scheme and risk management measures and
options should address) shall be the 1% AEP event, with provision for adaptability to the MRFS (see Section 5.5, and
Appendix C). However, where there is a clear technical, economic, social or environmental case as to why the preferred
standards would not be appropriate or acceptable, or where the adoption of alternative standards would provide
significant additional benefit in relation to costs and impacts, the Consultant shall consider and develop and assess the
Scheme and other actions and measures, as set out herein, to meet alternative design standards.
Notwithstanding the above, the Consultant shall consider flood risks associated with more significant events than those
of the preferred or proposed design standard (e.g., 0.1% AEP) as part of the appraisal to assess the impacts of failure of
the Scheme or other measures, and, if appropriate, for inclusion in design of the Scheme and measures.
Where no major structural flood protection Scheme is viable for the APSR, the Consultant shall assess localised or low-
scale structural protection measures (e.g., raising existing defences, infilling gaps in defences, creating minor defences
not requiring major structural works, etc.) to determine whether some protection (to a design standard that may be
less than the preferred design standard), would be beneficial and viable. Such measures may compliment other non-
structural measures that have been determined to be viable.
10.3 FLOOD RISK MANAGEMENT METHODS
A flood risk management option (‘option’) consists of one, or, more commonly, a combination of FRM methods, or
elements of such methods.
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The Consultant shall consider all possible structural and non-structural methods (i.e., techniques or approaches that
may be used to prevent flooding, or reduce, mitigate against or manage flood risk), which may be of localised application
and benefit (for example, structural flood defences or floodplain preservation through land zoning for a specific area)
or of broader application and benefit (such as the use of distributed upland storage or a catchment-wide flood
forecasting and warning system), and shall include, but not necessarily be limited to, those listed in Appendix G.
10.3.1 Flood Forecasting Systems
The Consultant shall analyse the potential for the development of an effective flood forecasting system or systems for
the APSR, and shall report on such analysis under the potential flood risk management options in the Draft Final Report
(Section 11.2). The analysis shall include the assessment of:
The potentially available advance forecast periods
The potential accuracy and reliability of the forecasts, including the impacts on accuracy and reliability caused by
the spatial variation of rainfall, localised hydraulic effects and infrastructure used (i.e., use of fluvial and / or rainfall
gauging stations, turlough depth gauges) etc.
The infrastructure that would be required, including recommended site locations for fluvial and / or rain gauging
stations and / or turlough depth gauges, justification for the number and location of gauging stations etc.
Maintenance requirements, this shall include ongoing yearly resources and expected life span of infrastructure.
As part of the analysis, the Consultant shall consider travel times of flood peaks, the location of existing and possible
gauging sites, the nature of the drainage network, degrees of uncertainty, costs of establishment and operation, etc.
The analysis shall not be required to include assessments of institutional capabilities. The Consultant shall not be
required to develop or implement the forecasting system under the Project, but rather assess potential viability and
benefits.
10.3.2 Strategic Sustainable Urban Drainage Systems
The Consultant shall analyse the potential for the development of sustainable urban drainage systems (SUDS) for each
APSR, and for sub-divisions of each APSR, at a strategic level, and shall report on (including maps and drawings as
appropriate) such analyses under the potential flood risk management options in the Draft Flood Risk Management Plan
(Section 10.9). The analysis shall for the APSR include the assessment of:
The natural drainage patterns
The potential for infiltration
The potential runoff rates (existing and potential future, including consideration of the potential future scenarios)
The storage volumes that might be required for detention ponds (for the APSR and sub-divisions, within swales,
road networks for extreme events, etc.)
The potential benefits with respect to water quality and achievement of the objectives of the Water Framework
Directive, as well as for the management of flood risks.
The responsibilities for management and maintenance of proposed systems (through discussion with the relevant
local authorities)
The safety aspects of proposed systems
The Consultant shall focus on the potential and requirements for SUDS for large areas (i.e., multiple, rather than
individual, development plots) but will not be required to develop detailed designs for the systems.
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10.4 SCREENING OF POSSIBLE FRM METHODS
The Consultant shall screen the identified possible FRM methods to identify those that might be applicable and viable
to address the risk and meet the defined objectives for the APSR.
The Consultant shall screen all of the possible FRM methods, including but not limited to those set out in Appendix G,
for their likely viability against a range of criteria, including:
Applicability to relevant area
Economic (potential benefits, costs, impacts – See Section 7 and Appendix D)
Environmental (potential benefits, impacts and opportunities – See Section 7 and Appendix E)
Social (social, legal and political acceptability, impacts on community development and sustainability, etc. – See
Section 7)
Cultural (potential benefits, impacts and opportunities – See Section 7)
The Consultant shall not be expected to design or develop the potentially viable FRM methods in any detail as part of
the screening process, but rather assess the FRM methods at a preliminary level to achieve an indicative appraisal
against the above criteria, to identify the potentially viable FRM methods that should be taken forward for consideration
in the formation of options and more detailed appraisal. Notwithstanding this, the Consultant shall soundly and robustly
justify the rejection of a FRM method from further consideration, with clear and transparent reasoning, on the basis of
at least one of the above criteria.
10.5 DEVELOPMENT OF POTENTIAL OPTIONS
The Consultant shall develop a range of potentially viable options for achieving the flood risk management objectives
for the APSR. Options are likely to incorporate one, or (more likely) a combination of, the FRM methods, or elements of
these methods, determined to be viable through the screening process (Section 10.4), and may include a mix of localised
and broader FRM methods. Each option shall constitute a potential response to meet the defined flood risk
management objectives, that could be taken forward and, if confirmed as an agreed preferred option, form an action
or measure as part of the Preferred Scheme or other action or measure.
10.6 APPRAISAL OF POTENTIAL OPTIONS
The Consultant shall appraise each and all of the potential options (Section 10.5), including where appropriate or
necessary the use of hydraulic modelling (for the modelled area of Kinvarra West, in conjunction with TCD) , to assess
the performance and impacts of the option in terms of:
Positive and negative economic, social, environmental and cultural impacts,
Impacts on flood risk elsewhere,
Sustainability (e.g., adaptability to future changes),
Health and safety aspects of construction, maintenance and operation, and,
Risk and uncertainty (i.e., robustness)
To assist with the appraisal, the Consultant shall assess each and all of the potential options against the objectives
(Section 7.4), in the form of a multi-criteria analysis. The appraisal shall involve scoring each and all of the options against
each objective in relation to specified minimum requirements (i.e., requirements for that objective that the option
should meet to be acceptable) and aspirational targets (i.e., targets that options should seek to achieve to be assigned
a maximum score for that objective), making use of defined indicators for each objective.
Under the appraisal, the Consultant shall determine appropriate scores for each option against each objective based on
their understanding of benefits, cost, impacts, etc., as appropriate, as derived from their work and information
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developed or received under the Project. The basis for the assignment of scores shall be quantitative where possible,
but otherwise qualitative, with the assignment of a score based on a description or category. In assigning scores for
each option with respect to each objective, the Consultant shall apply the Global Weighting (see below), and determine
and apply the Local Weighting (Section 7.4) appropriate to reflect the importance of that objective for the area in
question.
The OPW shall define the indicators, minimum requirements and aspirational targets, along with a ‘Global Weighting’
(national ranking of importance of each of the objectives), for each objective. The details of the multi-criteria analysis
and the indicators, minimum requirements and aspirational targets for each objective shall be reviewed and refined by
the Steering Group, subject to approval of GCC.
The Consultant shall soundly and robustly justify the assignment of scores under the appraisal within the Draft Final
Report (Section 10.9), with clear and transparent reasoning that should include quantitative evidence where reasonably
possible. In assigning the scoring of different options against different objectives, the Consultant shall follow guidelines
on default scoring (subject to variation based on local context), to be agreed by the Steering Group, subject to approval
of GCC, that will be developed to ensure consistency.
In the identification, development and appraisal of the options, the Consultant shall take into account all of the issues
and aspects to be taken into account in the preparation of flood risk management plans, as defined in Article 7(3) the
Directive on the assessment and management of flood risks (2007/60/EC).
Under the appraisal of options, the Consultant shall also identify and assess flood related measures being undertaken
under other policy areas including, but not necessarily limited to, national legislation and European directives as listed
under Annex A of the ‘Floods’ Directive, and shall identify and assess:
the actions or measures being, or proposed to be taken under other policy area,
their timing and duration,
their actual or possible impacts on flood hazard and risk within the APSR
opportunities or constraints they may provide or impose on options being appraised under the Project
10.7 SELECTION OF PREFERRED OPTIONS
Based on the appraisal set out under Section 10.6, the Consultant, in consultation with GCC, the OPW, the Steering
Group and Stakeholder Group, shall identify a preferred Scheme and other measures for the APSR. As part of the
identification process, the Consultant shall ensure that the preferred options should be:
as far as possible, viable against all criteria,
on balance across all criteria, the most beneficial option,
publicly and legally acceptable,
neutral or beneficial in relation to flood hazard and risk impacts upstream and downstream, and,
adaptable to, and/or provide for, potential future increases in flood hazard and risk
The identified preferred options shall form the preferred Scheme and other actions and measures, which the Consultant
shall develop and detail within the Final Report.
In consultation with GCC, the OPW, the Steering Group and Stakeholder Group, the Consultant shall prioritise the actions
and measures, according to their benefits relative to costs, taking account of potential budgets and the scale and
duration of the actions and measures.
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10.8 SPATIAL PLANNING AND IMPACTS OF DEVELOPMENT
The Consultant shall review the Development Plans, Local Area Plans and any other spatial planning documents relevant
to each APSR and each Unit of Management as a whole, including Plans or documents in force or in draft form at the
time of the review.
The Consultant shall discuss potential land use, spatial planning and development management policies, objectives,
zoning and issues with the planning departments of Local Authorities whose jurisdiction falls in part or in whole within
the APSR.
On the basis of the review and discussions, and with reference to all other work undertaken under the Project and to
the Guidelines on the Planning System and Flood Risk Management6, the Consultant shall develop high-level draft
recommendations for the consideration of flood risk in planning and development management for the APSR. The draft
recommendations should be outline in nature, and will not be required to address planning for individual plots or the
consideration of individual planning applications.
The Consultant shall discuss the draft recommendations with the planning departments of the relevant Local
Authorities, the OPW, the Steering Group and other key stakeholders as necessary, and report recommendations,
amended as necessary based on these discussions, in the Draft Flood Risk Management Plan (Section 11). Such
recommendations shall, where appropriate, form actions or measures to be included in the FRMP.
10.9 DRAFT FINAL REPORT
The Consultant shall prepare and submit to GCC a comprehensive Draft Final Report detailing the work undertaken and
the findings of Stage I of the Project, incorporating scaled drawings and plans of the preferred Scheme, including areas
likely to be inundated during flood storage, if appropriate, and maps of the benefiting areas. The Consultant shall also
provide to GCC all information and data collated or generated as part of Stage I of the project in a suitable digital format.
The Draft Final Report shall include, but not necessarily be limited to:
(i) An executive summary
(ii) An introductory section detailing the background and context of the Project
(iii) A detailed description of the hydrological analysis and of the hydraulic analysis and modelling undertaken
(iv) Details of the surveys and condition and structural assessments undertaken
(v) A detailed description of the Scheme analysis and development, including the options and defence standards considered, the cost-benefit and multi-criteria assessments of the options and the Standards of Protection considered, and a detailed description of the preferred Scheme.
(vi) Conclusions and recommendations
GCC, assisted by the Steering Group and other experts as deemed necessary by GCC, shall review the Draft Final Report
and submit observations to the Consultant within three (3) weeks of receipt.
The Consultant shall review the observations submitted by GCC, and prepare and submit to GCC second versions of the
Draft Final Report that suitably addresses the observations of GCC within two (2) weeks of receipt of the observations
from GCC.
GCC, assisted by the Steering Group and other experts as deemed necessary by GCC, shall, within two (2) weeks of
receipt, review the second version of the Draft Final Report to ensure that all observations have been appropriately
addressed. In the event that GCC does not consider that all observations have been appropriately addressed, GCC shall
submit further observations to the Consultant to be addressed by the Consultant as set out above. In the event that
6 Guidelines on the Planning System and Flood Risk Management, Dept. of Environment, Heritage and Local Authorities &
Office of Public Works (November 2009)
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GCC is satisfied that all observations have been appropriately addressed, the Consultant shall re-submit the Report as
the Final Report.
The Consultant shall submit four (4) hard copies of the Final Report.
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11 PREPARATION OF A FLOOD RISK MANAGEMENT PLAN
11.1 FLOOD RISK MANAGEMENT PLAN
The Consultant shall prepare a Flood Risk Management Plan (FRMP), including a 5-10 page executive summary that can
be read in isolation.
The FRMP shall briefly outline the Project and the flood risk assessment and analysis, and then clearly set out the Scheme
and other flood risk management policies, strategies, actions and measures (proposed) to be implemented by the OPW,
Local Authorities and other relevant bodies.
The FRMP will be publicly available, and shall be non-technical and suitable for use by politicians, stakeholders and the
public. The main text of the FRMP shall typically be in the order of 50-80 pages in length (excluding the executive
summary and appendices).
It is foreseen that the FRMP will be structured in the following format:
Introduction and Background
Statutory, Stakeholder and Public Consultation (including, where appropriate, a description of the cross-border
coordination)
Catchment Overview (description of the rivers and catchments)
Outcomes of the Preliminary Flood Risk Assessment
Outcomes of the Flood Hazard Assessment
Outcomes of the Flood Risk Assessment
Flood Risk Management Objectives
Environmental Considerations (including a summary of the EIAR, and a description of the coordination with the
River Basin Management Plans prepared under the Water Framework Directive)
Flood Risk Management Options (including a brief outline of the method and option appraisal and prioritisation
processes)
Programme of Work (including a prioritised and costed programme of the policies, strategies, actions and measures
to be implemented by the OPW, Local Authorities or other relevant bodies, including those under other policy
areas)
Plan Monitoring and Review
The text and images for the section of the FRMP on ‘Outcomes of the Preliminary Flood Risk Assessment’ shall be
provided by the OPW, but the Consultant shall incorporate this into the FRMP, including any formatting, etc., as
necessary.
Appendices to the FRMP, or linked separate volumes referenced within the FRMP, shall include, but not necessarily be
limited to:
A list of the relevant Competent or Responsible Authorities
Flood hazard (Section 6.4) and risk (Section 7.3) maps
A detailed list of objectives, indicators and targets
A description of options appraised as set out under Section 10.6 herein
A description, including maps, drawings, etc. of the measures included in the FRMP
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11.2 SUBMISSION OF FLOOD RISK MANAGEMENT PLAN
The Consultant shall submit a Draft FRMP (Section 11.1), and shall supply the following as part of, or as an
accompaniment to, the Draft FRMP:
Report on spatial planning and impacts of development (Section 10.8)
Flood Risk maps, as detailed in Section 7, and associated GIS / attribute digital data
GCC, assisted by the Steering Group and other experts as deemed necessary by GCC, shall review the Draft Flood Risk
Management Plan and submit observations to the Consultant within three (3) weeks of receipt.
The Consultant shall review the observations submitted by GCC, and prepare and submit to GCC second versions of the
Draft Flood Risk Management Plan that suitably addresses the observations of GCC within two (2) weeks of receipt of
the observations from GCC.
GCC, assisted by the Steering Group and other experts as deemed necessary by GCC, shall, within two (2) weeks of
receipt, review the second version of the Draft Flood Risk Management Plan to ensure that all observations have been
appropriately addressed. In the event that GCC does not consider that all observations have been appropriately
addressed, GCC shall submit further observations to the Consultant to be addressed by the Consultant as set out above.
In the event that GCC is satisfied that all observations have been appropriately addressed, the Consultant shall re-submit
the Plan as the Final Flood Risk Management Plan.
The Consultant shall submit four (4) hard copies of the Final Flood Risk Management Plan.
The Consultant shall supply the following as part of, or as an accompaniment to, the Final Flood Risk Management Plan
final sets of all reports, maps, model files and all other data connected with or used for the Project.
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12 REPORTING AND DELIVERABLES
12.1 REPORTING STANDARDS
All reports, draft and final, submitted by the Consultant shall be detailed and clear and have been proofread to correct
any grammatical or typographical errors, and shall:
Provide full and comprehensive descriptions of topics covered,
Detail any assumptions made, including the requirement for the assumption and the justification for the
assumption made,
Support any statements made with relevant discussion and justification,
Provide (in appendices if necessary) all data, maps and information relevant to the topics covered.
12.2 DELIVERABLES
The Consultant shall supply to GCC the documents, data, files and other material detailed herein with the reports (in
both draft and final versions) under which it is listed. Provision of the deliverables is a pre-requisite for payment against
the relevant milestone.
Unless otherwise stated, the Consultant shall only be required to provide digital copies of each report or deliverable.
The spatial information forming the basis of all maps should be provided in GIS format. Selected maps (as specified
within this document) and all drawings should be provided in Print-Ready Format.
The Consultant shall provide to GCC six (6) hard copies of the Final Report.
All reports and deliverables, both draft and final, shall be supplied in editable digital format compatible with the
Microsoft Office 2013 (i.e. .doc,.xls,.ppt etc), ArcGIS, MapInfo or AutoCAD (AutoCAD 2007 format is not acceptable. DXF
is preferred) as appropriate, and also in Adobe Acrobat ‘pdf’ format.
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APPENDIX A
PRELIMINARY RISK ASSESSMENT FOR SITE WORK
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Ref. Risk Hazard Consequence Likelihood of Occurrence Impact to Health Level of Risk
Actions to be Taken to Remove, reduce or mitigate the risk Level of Risk Post Mitigation
Low Medium High Low Medium High Low Medium High Low Medium High
1
To other Road Users
National Routes
Local Routes
Personal Injury. Possible Fatalities
Material Damage, Injury to Others
Low Medium Medium
1. High Visibility Clothing to be worn at all times
2. Use Approved Motorway Maintenance Signs if required
3. Use Approved yellow flashing beacons on vehicles
4. Do not park in a position likely to obstruct other motorists
5. All vehicles to be in roadworthy condition
Low
2 Trains, Rail Crossings
Personal Injury, Possible Fatalities
Material Damage, Injury to Others
Low High High
1. Do not enter onto Railway Property without prior consent of Irish Rail
2. Observe and comply with Health and Safety requirements of Irish Rail.
Low
3
To Landowners from Machinery Striking
Surveying Pegs
Personal Injury, Injury to Others.
Material Damage
Medium Medium Medium
1. Place markers in boundaries away from where machinery will operate
2. All surveying pegs and nails to be driven flush into ground
3. Remove unwanted markers after survey
4. All pegs and nails to be clearly marked with high visibility paint / flag
Low
4 Injury from Animals /
Livestock
Personal Injury,
Injury to Others Low Medium Medium
1. Do not enter field or area with dangerous livestock
2. Arrange alternative safe access if possible
3. Request owner to remove dangerous livestock before entering
4. Do not leave closed gates open
Low
5 Obstructions Personal Injury,
Injury to Others Low Low Low
1. Ensure that that all survey equipment is not set-up in such a manner not to cause an obstruction
2. Ensure that all pegs and nails will not cause as tripping hazard
3. Provide protective barriers and/or assistance as required.
Low
6 General Accidents
Cuts, Bruises etc. Personal Injury Medium Low Medium
1. Approved First Aid Kit must be provided / available to all staff
2. Ensure that staff are aware of nearest A&E locations and have contact details
3. Have emergency telephone numbers issued to staff and stored in memory of mobile phones.
4. Where possible have a staff member trained in First Aid on each survey team
5. Wear personal protective equipment (i.e. PPE), Maintain in good order, replace damaged defective items.
Low
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7 Working Near to River
/Water
Personal Injury.
Possible Fatalities Medium High High
1. Wear Life Jackets/ floatation device at all times when near water
2. Immersion suit or wet suit to worn as appropriate
3. Maintain and check all PPE before use.
4. All surveying teams to carry minimum of two mobile phones
5. Work rota and locations to be agreed daily with project manager
6. A boat will be used in deep/fast flowing water
7. Only enter into water where depth does not exceed 1 metre depth, approved waders must be worn
8. Teams of two will operate where water levels are low enough not to constitute a safety risk
9. Teams of three required when a boat is in use
10. Life Buoy and Secure Rope to be provided at all times when near water
Low
8 Launching Boats Personal Injury.
Possible Fatalities Medium Low Medium
1. Choose a suitable and safe location to access the water
2. Launch and secure boat prior to loading
3. Ensure enough staff are present to lift boat and equipment comfortably
Low
9 Working from Boats Personal Injury.
Possible Fatalities Medium High High
1. Wear Life Jackets/ floatation device at all times when near water
2. Maintain and check all PPE before use.
3. Arrange secure rope across water to hold boat in position.
4. All boat crews to be instructed and trained in proper and safe use of boat
4. Seek permission of relevant authorities when using boats in waters used by other boats and shipping
Low
10 Boat Engine / Fuel
Storage
Muscular, Ligament or joint injury.
Risk of Fire and Burns
Risk of lacerations, cuts and bruises
Low Low Low
1. Boat Engine to be moved / fitted by two staff members
2. Fuel to be stored and transported in approved sealed containers.
3. Wait for engine to cool before removal
4. Ensure that propeller is in the water and free from obstructions before starting.
Low
11 Mud - Slipping Personal Injury High Medium High 1. Wear safety boots with thick cleated non slip soles
2. Use rope and wear gloves Low
12 Weil's Disease Hazard to Health Low Medium Medium
1. Cover cuts and wear suitable gloves
2. Wash hands before eating, smoking of bringing hands in contact with mouth
3. Provide suitable disinfectant cleaning liquid / wipes
4. Wear approved waders when in water.
Low
13 Submerged Objects
Broken Bones, Bruises,
Lacerations,
Medium Medium Medium
1. Before entering water undertake visual inspection for potential hazards
2. Never enter water without suitable protective footwear
Low
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3. Move cautiously if in water
14 Potential Health
Hazards
Broken Bones, Bruises, Lacerations,
Hazard to Health
Medium Medium Medium
1. Review all sites and banks for potential health hazards, (e.g. Discarded hypodermics, broken glass etc)
2. Do not handle any such potential health hazards,
3. Do not enter water if in doubt
Low
15 Sudden Peak Flow/
Water Release/ Tidal Exposure to risk of
drowning Medium High High
1. Liaise with barrier control staff and advise when working in channel
2. Check tide tables daily
3. Check weather forecast daily and monitor conditions.
4. Liaise with ESB
Low
16 Falling from Heights Broken Bones,
Bruises, Lacerations, possible fatalities
Low High Medium 1. Observe the working at heights regulations Low
17 Injury from Above
(Falling masonry)
Personal Injury -Possible Fatalities
Medium Medium Medium 1. Do not enter spaces at risk from falling objects such as loose
masonry without required PPE Low
18 Confined Spaces Personal Injury -
Possible Fatalities Medium High High
1. Do not enter any confined space, unless trained and appropriately equipped with required PPE
2. Inform Client if need to enter confined space is required.
Low
19 Access Personal Injury Medium Medium Medium
1. Agree work locations daily with Project Manager
2. Special care to be taken when accessing remote sites, (Crossing boundaries, gates, fences etc.)
3. Special care to be taken when working or crossing fields where animals are grazing.
4. Use safe access routes in and out of the sites and around sites.
Low
20 Site Vehicles /
Transportation to site
Material Damage, Personal Injury
Injury to Others
Low Medium Medium 1. Must be driven by a competent and authorised person. Low
21 Working near high voltage power lines and other services
Possible fatalities due to electrocution
Injury to others
Medium High High
1. Observe guidelines issued by Electricity Supply Board and Health & Safety Authority
2. Ensure that no contact is possible with either overhead or underground cables.
3. If unable to work safety at site due to overhead/underground cables inform Project Manager re: alternative location
Low
22 Manual Handling Muscular, Ligament
or joint injury Medium Medium Medium
1. Observe best practice manual handling techniques when lifting and carrying
2. Ensure enough staff are present to lift /carry equipment comfortably
Low
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23
Release of Possible Contaminants
from Mud / Sediments from Bed
of River Channel
Injury to Health, Damage to Aquatic
Environment and Water Quality
Medium Medium Medium
1. Check known and or possible locations with Client prior to commencement of Survey
2. Minimise need to entry water and/or possible disturbance of muds and sediments
3. If type of contaminant known consult with competent authority regarding possible risks
4. Cover cuts and wear suitable gloves and PPE
5. Comply with recommendation from Environmental and Health Authorities
6. Provide suitable disinfectant cleaning liquid / wipes / Washing facilities
Low
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APPENDIX B
REGISTER OF RELEVANT REPORTS
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(1) An Investigation of the Flooding Problems in the Gort- Ardrahan Area of South Galway April 1997 –
SWG & JOD on Behalf of the OPW
(2) N17 / N18 Gort to Tuam PPP Scheme February 2010 – HyderTobin – 2009 Flooding Report
(3) 2010-2011 Review of the South Galway Flood Study Report – Jennings O’Donovan Consulting Engineers
on behalf of OPW
a. Review of the Recommendations and Conclusions of the Mannin Cross, Kilchreest & Termon 2003 Flood
Alleviation Schemes December 2010
b. Engineering Proposals for the Reinstatement of Culverts on the N18 and the Provision of New
Culverts on Minor Roads at Kiltartan & Feasibility of an Overland Channel from Coole to
Kinvarra September 2011
c. Review of Recommendations on Key Arterial & Essential Access Routes, Planning Controls & Data
Collection April 2011
(4) Engineering Proposals for Restoration Works to Mitigate Flood Risk Kiltartan to Kinvarra November
2011 – ARUP – Environmental Report
(5) Termon North Flood Alleviation Scheme July 2014 – Ryan Hanleys - NIS
(6) Dunkellin River and Aggard Stream Flood Relief Scheme October 2014 – RPS - NIS & EIS Reports (note
findings regarding effects on local oyster farms from proposed scheme) – available to view at
http://www.galway.ie/en/services/roads/dunkellindrainagedistrict/
(7) Completion & Remediation of Emergency Flood Alleviation Works from Cahermore to Kinvarra
September 2016 – McCarthy, Keville, O’Sullivan – EIA & AA
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APPENDIX C
ASSESSMENT OF POTENTIAL FUTURE SCENARIOS
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C1 INTRODUCTION
C1.1 Background
It is widely predicted that the climate in Ireland will change in the future, leading to increases in sea level,
storm event magnitude and frequency, and rainfall depths, intensities and patterns. These impacts, along
with others due to land use changes such as urbanisation and deforestation, are likely to have significant
detrimental implications for the degree of flood hazard, and hence flood risk, in Ireland. The degree of these
impacts over time are, however, subject to significant uncertainty.
C1.2 Future Scenarios and Allowances
C1.2.1 Future Scenarios
To provide an adequate understanding of the potential implications of the predicted impacts of climate change and
other future changes, with due consideration of the significant uncertainty associated with such predictions, the
Consultant shall assess a minimum of two potential future scenarios.
The two minimum scenarios are referred to as the Mid-Range Future Scenario (MRFS) and the High-End Future Scenario
(HEFS), as described below:
The former (the MRFS) is intended to represent a ‘likely’ future scenario, based on the wide range of predictions
available and with the allowances for increased flow, sea level rise, etc. within the bounds of widely accepted
projections.
The latter (the HEFS) is intended to represent a more extreme potential future scenario, but one that is nonetheless
not significantly outside the range of accepted predictions available, and with the allowances for increased flow,
sea level rise, etc. at the upper the bounds of widely accepted projections.
In certain circumstances, where very significant risk exists or exceptional investment is being considered, the use of
further scenarios, particularly extreme scenarios, should be considered.
C1.2.2 Allowances for Future Scenarios
The allowances, in terms of numerical values for future changes to 2100 in relevant phenomena or characteristics, which
should typically be used for each of these scenarios, are set out in Table F1 below.
Table C1: Allowances for Future Scenarios (Time horizon – 100 years)
MRFS HEFS
Extreme Rainfall Depths + 20% + 30%
Flood Flows + 20% + 30%
Mean Sea Level Rise + 500 mm + 1000 mm
Land Movement - 0.5 mm / year1 - 0.5 mm / year1
Urbanisation No General Allowance – Review on
Case-by-Case Basis No General Allowance – Review on
Case-by-Case Basis
Forestation - 1/6 Tp2 - 1/3 Tp2
+ 10% SPR3
Note 1: Applicable to the southern part of the country only (Dublin – Galway and south of this)
Note 2: Reduce the time to peak (Tp) by a third: This allows for potential accelerated runoff that may arise as a result of drainage of
afforested land
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Note 3: Add 10% to the Standard Percentage Runoff (SPR) rate: This allows for increased runoff rates that may arise following felling
of forestry.
The following should however be noted:
The allowances are based on current knowledge and science, and will be frequently reviewed and may be updated,
as further research is undertaken. {In that regard please see below the Executive Summary from the OPW Climate
Change Sectoral Adaptation Plan, Flood Risk Management(2015-2019)}
C2 CLIMATE CHANGE SECTORAL ADAPTATION PLAN
Outlined below is the Executive Summary from the OPW Climate Change Sectoral Adaptation Plan, Flood Risk
Management (2015-2019).
The complete document will be available on request.
Executive Summary
A Flood Risk Management Climate Change Adaptation Plan has been prepared under the remit of the National Climate
Change Adaptation Framework. It sets out the policy on climate change adaptation of the Office of Public Works (OPW),
the lead agency for flood risk management in Ireland, based on a current understanding of the potential consequences
of climate change for flooding and flood risk in Ireland, and the adaptation actions to be implemented by the OPW and
other responsible Departments and agencies in the flood risk management sector.
Background
Adapting to climate change is a key challenge facing Governments and societies across the world. It is now clear that,
even if the climate change mitigation measures undertaken to date are successful, climate change will not stop over the
coming decades or possibly centuries. Adapting to its impacts is necessary to reduce vulnerability across all sectors of
Society and the Natural Environment. Recognising this challenge, the Irish Government published the National Climate
Change Adaptation Framework in December 2012, which sets out Government policy for addressing climate change
adaptation in Ireland. It focuses on key climate sensitive sectors and mandates certain Government Departments, other
public sector bodies and Local Authorities to prepare sectoral and local climate change adaptation plans. The OPW was
assigned the task of preparing the Sectoral Adaptation Plan for Flood Defence, or Flood Risk Management (FRM), sector.
The scope of the Flood Risk Management Climate Change Adaptation Plan includes:
− A review of the existing science relating to the potential impacts of climate change on flooding.
− An outline of the potential increase in flood hazard and flood risk due to climate change, drawing on the work done
under the National Catchment-based Flood Risk Assessment and Management (CFRAM) Programme, including
information for other sectors.
− An overview of current areas of work in the flood risk management sector.
− A policy and actions for climate change adaptation to be pursued and applied by the OPW and other responsible
Depts. / agencies in the development of flood risk management strategies and measures. Detailed adaptation
approaches and measures, to a specified programme, will be set out in the Flood Risk Management Plans (FRMPs) being
developed under the CFRAM Programme.
The Flood Risk Management Climate Change Adaptation Plan does not specify how other sectors should provide for
potential climate-related changes in flood hazard and risk. It provides information on the potential change for
consideration by those sectors. The Sectoral Adaptation Plan is set out below in Table C2.
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Flooding in Ireland
Flooding, as defined in the EU 'Floods' Directive, is a temporary covering by water of land that is normally dry, and is a
natural process that can happen at any time in a wide variety of locations. Flood hazard is the potential threat posed by
flooding to people, property, the environment and our cultural heritage. The degree of hazard is dependent on a variety
of factors that can vary from location to location and from one flood event to another. These factors include the extent
and depth of flooding, the rate of flow or velocity over the floodplains, the rate of onset and the duration of the flood.
Flooding can occur from a range of sources, including:
− Coastal flooding, from the sea and estuaries
− Fluvial flooding, from rivers, lakes and streams
− Pluvial flooding, where intense rainfall leads to overland flow and ponding
− Groundwater flooding, particularly from turloughs after prolonged wet periods
− Flooding from infrastructure, such as from reservoir breaches or blocked or surcharged piped networks
Flooding only presents a risk when people, property, the environment and our cultural heritage can be potentially
damaged by floods. Flood risk is dependent on the probability and magnitude of the flood hazard and the vulnerability
of society, infrastructure and our environment to damage or loss in the event of a flood.
Ireland has a long history of flooding, which has been identified by the Government Task Force on Emergency Planning
in the National Risk Assessment developed by the Office of Emergency Planning (OEP) as one of the two most
significant risks facing Ireland today (OEP, 2012). The National Historic Flood Event Database, publicly available
through a website (www.floodmaps.ie), contains records of nearly 5,500 past flood events dating back to 1763.
The floods of November 2009 would in many ways have been the most exceptional on record; both in scale and
extent. The event was truly national, with many rivers across the country reaching record levels, including the River
Shannon that substantially exceeded the highest levels previously recorded over a period of about 100 years. Cork City
also suffered its first major river flood in the decades since the hydropower reservoirs were constructed on the River
Lee upstream.
The National Preliminary Flood Risk Assessment (PFRA) analysed the flood risk nationally to identify areas where the
risk is potentially significant. These areas, referred to Areas for Further Assessment (AFAs), are the focus of the
National CFRAM Programme, through which detailed flood maps are being prepared, and measures aimed at
managing and reducing the flood risk will be developed, appraised and set out in a set of Flood Risk Management
Plans (FRMPs).
Flood Risk Management in Ireland
Flood risk management in Ireland has developed over time from having an initial focus on the drainage of agricultural
land, to providing localised flood relief schemes for urban areas, to taking a catchment-based and pro-active approach
to assess and manage risks. This latter approach was established following adoption of the recommendations of the
National Flood Policy Review (OPW, 2004) and was subsequently reinforced by the EU approach to flood risk
management as set out in Directive 2007/60/EC (the EU 'Floods' Directive). The OPW, as the lead agency for flood risk
management in Ireland, is responsible for coordinating the implementation of the National Flood Policy and the EU
'Floods' Directive. It is fulfilling many of these obligations through the National CFRAM Programme.
The current areas of FRM activity in Ireland being undertaken by the OPW and other organisations include:
− Rural land drainage and flood protection, provided through the maintenance of Arterial Drainage Schemes, Drainage
Districts and Land Commission Embankments
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− Flood Protection, provided through Flood Relief Schemes and Minor Works, and the design and maintenance of
urban storm water and other infrastructure
− Flood Prevention, by way of sustainable planning and development
− Flood Preparedness, Response and Resilience, provided through public information campaigns, flood forecasting and
warning, effective flood emergency response planning and building individual and community resilience
− Risk assessment and management planning, including the collection of hydrological and flood data, and the National
PFRA and CFRAM Programmes
Impacts of Climate Change on Flood Risk
It is likely that climate change will have a considerable impact on flood risk in Ireland.
− Sea level rise is already being observed and is projected to continue to rise into the future, increasing risk to our coastal communities and assets, and threatening coastal squeeze of inter-tidal habitats where hard defences exist.
− It is projected that the number of heavy rainfall days per year may increase, which could lead to an increase in both fluvial and pluvial (urban storm water) flood risk, although there is considerable uncertainty associated with
projections of short-duration, intense rainfall changes due to climate model scale and temporal and spatial down-scaling issues.
− The projected wetter winters, particularly in the West of the country, could give rise to increased groundwater flood risk associated with turloughs.
These potential impacts could have serious consequences for Ireland, where all of the main cities are on the coast and
many of the main towns are on large rivers.
While there is considerable uncertainty associated with most aspects of the potential impacts of climate change on
flood risk, it is prudent to take the potential for change into account in the development of FRM policies and strategies
and the design of FRM measures.
The National CFRAM Programme is central to the assessment of future flood risk and the planning of future FRM
activity in Ireland, and was designed as the vehicle through which climate change adaptation policies would be
implemented with respect to flood defence. It will hence be the cornerstone of climate change adaptation in the
sector. This Programme includes the assessment of risk for two potential future scenarios; the Mid-Range Future
Scenario (MRFS) and the High-End Future Scenario (HEFS). These scenarios include a sea level rise of 0.5m and 1.0m
and an increase in peak flood flows of 20% and 30% for the MRFS and HEFS respectively.
Preliminary assessments of potential future risk broadly indicate that flood risk will increase substantially in terms of
the frequency of extreme events and the degree of risk nationally. The impacts are however highly variable between
different areas, and vulnerability assessments will need to be undertaken on a community-by-community
basis to determine locally-specific changes in risk and hence appropriate adaptation responses. Through the CFRAM
Programme and future cycles of implementation of the EU 'Floods' Directive, the potential impacts of climate change
and other socioeconomic changes will be assessed and reviewed on an ongoing basis.
Adaptation Policies
Guidance and information on adaptation to climate change is provided by the United Nations Framework Convention
on Climate Change (UNFCCC), the Intergovernmental Panel on Climate Change (IPCC) and the European Union. This is
supplemented nationally by the National Climate Change Adaptation Framework (DoECLG, 2012) and research by the
Environmental Protection Agency (EPA). An appropriate adaptation approach needs to include:
− Assessments of future changes in hazard, vulnerability and risk
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− Planning for adaptation, including the identification of adaptation policies and actions that should provide for flexible, 'no regrets' strategies and measures that can be adapted to ongoing change through a managed adaptive approach
− Implementation of adaptation measures, with adaptation embedded into mainstream programmes
− Monitoring, evaluating and updating adaptation plans
− Ensuring coordination in adaptation panning between sectors
Sectoral Adaptation Requirements
The OPW has adopted the following policy with respect to climate change adaptation:
The possible impacts of climate change, and the associated uncertainty in projections, shall be considered at all stages
of activity under the national Flood Risk Management Programme, and the development, design and implementation
of all policies, strategies, plans and measures for, or related to, flood risk management must be sustainable and
cognisant of the potential impacts of climate change.
Under this policy, each flood risk management activity has been examined to determine what actions are required to
embed and provide for effective adaptation with respect to flood risk. These include actions, which should be
implemented by the OPW and/or other organisations as appropriate, in the following areas:
− research,
− hazard and vulnerability assessment,
− the design, implementation and maintenance of flood risk management measures,
− capacity building,
− monitoring and review, and,
− adaptation planning and governance
The adaptation actions are set out in a tabular format in Section 7 of this Plan.
Adaptation for Other Sectors with respect to Flood Risk
Flooding is a cross-sectoral issue that can affect all aspects of life, and that can be influenced, positively or
detrimentally, by actions in many other sectors. It is recommended that other sectors consider flood risk as part of
their adaptation processes, making use of the information that has been and will be available from the OPW or via the
'Climate Ireland' Platform. Of particular importance is the consideration of potential future flooding environments in
the area of planning and development management, and the planning and design of infrastructure.
SEA and Natura Impact Screening
This Plan has been screened with respect to the potential need for a Strategic Environmental Assessment and
Appropriate Assessment.
The SEA screening process undertaken by the OPW was in accordance with the European Communities (Environmental
Assessment of Certain Plan and Programmes) Regulations 2004 (S.I. No. 435 of 2004) and amending Regulations, (S.I
200 of 2011).
The Appropriate Assessment Screening Report was produced in line with the requirements of Article 6(3) of the EU
Habitats Directive (Directive 92/43/EEC).
It has been concluded with respect to both, that assessments are not required.
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See Table C2 below which outlines the Summary of Adaptation Actions Summary from the OPW Climate Change
Sectoral Plan, Flood Risk Management (2015-2019)
Table C2: Summary of Adaptation Actions
REF ACTION: Research Who When
A.1 Improve, through research, the understanding of likely future
changes in seasonal and short- duration rainfall patterns and the
frequency of occurrence and severity of weather storms to
inform future assessments.
EPA, Met.
Eireann
Ongoing
A.2 Assess, through research, the impacts of future changes in
seasonal and short-duration rainfall patterns on land saturation
and water-logging, and resultant effects on farming.
DAFM Ongoing
A.3 Address information needs to improve adaptation to potential
flood risk futures through research on the drivers of change to
the climatic parameters related to flooding and on how such
changes will manifest in changes in flood hazard.
OPW, EPA &
Met. Eireann
Ongoing
A.4 Address information needs to improve adaptation to potential
flood risk futures through research on communication and
community awareness and action in adaptive flood risk
management and on decision-making under uncertainty for
dissemination through the 'Climate Ireland' web platform.
OPW, EPA &
Local
Authorities
Ongoing
Ref Action: Assessment Who When
B.1 Assessment and publication of flood hazard and risk mapping for
the MRFS and HEFS for the AFAs through the National CFRAM
Programme.
OPW 2016
B.2 Potential impacts of climate change on the standard of
protection for existing flood relief schemes to be reviewed as
part of National CFRAM Programme.
OPW 2016
B.3 As part of the review of the PFRA, assess, based on available and
readily-derivable information, the existing and potential future
standard of protection and benefits of the Land Commission
embankments.
OPW & DAFM 2018
B.4 As part of the review of the PFRA, assess the existing standard
of protection and condition and benefits of the Arterial Drainage
Scheme Embankments, and assess the costs, benefits, merits
and impacts of maintenance or improvement of the
embankments to inform future work.
OPW 2018
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B.5 Review of the National PFRA including assessment of the
potential impacts of climate change to provide a regular
assessment of the national vulnerability to the potential impacts
of climate change on flood risk.
OPW 2018
B.6 Assessment and publication of flood hazard and risk mapping for
areas of potentially significant risk identified through future
cycles of the PFRA.
OPW 2019 &
Ongoing
B.7 Review of the PFRA with respect to existing urban storm water
flooding, including assessment of the potential impacts of
climate change, and where relevant, prepare flood maps and
assess measures, where reasonably possible, to reduce or
manage the flood risk from urban storm water management
systems.
Local
Authorities
2018 &
Ongoing
B.8 Review of the PFRA with respect to existing infrastructural
assets that could give rise to flooding or flood risk, including
assessment of the potential impacts of climate change, and
where relevant, prepare flood maps and assess measures to
reduce or manage the flood risk from those assets.
Local
Authorities, ESB,
Waterways &
Irish Water
2018 &
Ongoing
Ref ACTION: Planning, Design & Implementation Who When
C.1 Flood risk management strategies and outline designs for
potential flood risk management measures are to be developed
through the National CFRAM Programme based on the adaptive
management approach, in coordination with the preparation of
the RBMPs, and set out in the FRMPs.
OPW 2016
C.2 Identify, as part of the preparation of the FRMPs being produced
under the National CFRAM Programme, additional hydrometric
monitoring needs with respect to monitoring or assessing the
potential impacts of climate change on flood risk for vulnerable
communities.
OPW 2016
C.3 Appropriate adaptation options for each existing flood relief
scheme to be assessed in the review of the first FRMPs, with any
necessary measures to be set out in the second cycle FRMPs.
OPW 2016-
2021
C.4 Decisions on short-term investment in flood risk management
measures should include a detailed review and determination of
the most robust, 'no regrets' strategy and design, taking account
of the range of future investments that may be necessary
depending on how the impacts of climate change are
manifested with respect to flood risk.
OPW Ongoing
C.5 Proposals submitted under the Minor Works Programme should
take account of the potential impacts of climate change to
Local
Authorities
Ongoing
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ensure that any measures proposed are adaptable to possible
future changes.
C.6 Ensure that potential future flood information is obtained
and/or generated through a Flood Risk Assessment (FRA) that is
then used to inform suitable adaptation requirements within
planning and development management in line with the
Guidelines on the Planning System and Flood Risk Management
(DoECLG & OPW, 2009).
Planning
Authorities &
Developers
Ongoing
C.7 Maintain and update on an ongoing basis the National Flood
Event Database (www.floodmaps.ie).
OPW Ongoing
C.8 Maintain, and where possible improve, the operation of existing
flood forecasting and warning systems, including the Tide and
Storm Surge Forecasting Service.
OPW, Relevant
Local Authority
Ongoing
C.9 Identify the benefits and resources required to develop, on a
phased basis, a national flood forecasting and flood warning
service, for decision by Government.
OPW, DECLG &
DPER
Ongoing
C.10 Ensure that flood event emergency response plans are reviewed
on a regular basis to reflect the degree of flood risk and/or our
understanding of that risk, including the resource capacity
required to provide an effective response.
Local
Authorities &
DECLG
Ongoing
C.11 The requirements for urban storm water drainage systems for
new development should take into account the potential future
impacts of climate change, including consideration of the use of
sustainable drainage systems.
Local
Authorities
Ongoing
C.12 The planning and design of future assets should take into
account, and be adaptable to, the potential future impacts of
climate change.
Local
Authorities, Irish
Water, ESB &
Waterways
Ireland
Ongoing
Ref
ACTION: Capacity Building Who When
D.1 Implement the recommendations of the report of the Inter-
Departmental Flood policy Co- ordination Group, due in Summer
2016.
Cross-
Government
Ongoing
D.2 Strengthen the adaptive capacity of OPW staff and partners
through collaboration and training.
OPW Ongoing
D.3 OPW to make available relevant information for access and
dissemination through 'Climate Ireland' web platform.
OPW, EPA Ongoing
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Ref ACTION: Monitoring & Review Who When
E.1 Develop indicators to assess effectiveness and implementation
of adaptation within the flood risk management sector, with
reporting on same in the next Plan.
OPW 2016-
2019
E.2 Progress reviews will be undertaken at three yearly intervals
(end of 2016 and 2019), or as otherwise required under new
legislation or EU requirements, on the implementation of this
Plan and progress in integrating adaptation into flood risk
management.
OPW 2019
Ref ACTION: Planning & Governance Who When
F.1 Local Adaptation Plans, and Adaptation Plans for other Sectors,
should take account of the potential impact of climate change
on flooding and the effects the foreseen increases in flooding
and flood risk may have locally and on each Sector, and also how
adaptation decisions taken locally and in other sectors may
impact on flooding and flood risk. This would benefit from
ongoing information exchange and coordination through cross-
sectoral fora such as the Adaptation Steering Group convened
by DCELG.
Local
Authorities, All
Sectors
2015 and
Ongoing
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APPENDIX D
CALCULATION OF ECONOMIC DAMAGES
AND COST BENEFIT ANALYSIS
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D1.0 METHOD FOR ECONOMIC DAMAGE ASSESSMENT AND COST BENEFIT ANALYSIS - PURPOSE
The purpose of this Note is to set out a common approach to the calculation of monetarised, economic
flood damages and the economic benefits of flood risk management options, and for undertaking a cost-
benefit analysis.
D2.0 SCOPE
This Note relates to the calculation of monetarised, economic flood damages and the potential economic
benefits of options for flood risk management measures, for the purposes of:
The calculation of the economic (monetary) benefit-cost ratio for options for flood risk management
measures (to be used for option appraisal)
Option appraisal against Objective 2.a (Minimise Economic Risk) under the Multi-Criteria Analysis
(MCA)
Note that there are minor variations in the benefit / damage values to be used for the two purposes
above (see Section 4.5 herein).
This Note does not address:
The calculation of the costs of options for flood risk management measures
The application of the Multi-Criteria Analysis (MCA) to appraise flood risk management measures
(except for Objective 2.a)
A glossary of abbreviations / acronyms used for this Note is provided in Appendix A. An explanatory table
is provided in Appendix B, which might be useful for clarity.
D3.0 CALCULATION OF ECONOMIC FLOOD DAMAGES
D3.1
General Requirements
The requirements for the calculation of economic risk, and hence economic flood damages are as set out
in this Note.
General Methodology
The calculation of flood damages should be based on the Flood Hazard Research Centre Handbook for
Economic Appraisal of 2014 (FHRC, 2014 - the ‘Multi-Coloured Manual’), subject to caveats, amendments
and clarifications set out herein.
Where the depth-damage data provided in FHRC provides unusual or extreme results, the Consultant
should refer to the OPW for guidance.
Price Conversions
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Prices (damage costs) in the data provided by FHRC 2014 should be converted to euro rates applicable
to Ireland in 2016 by:
- Applying a ‘PPP’ multiplication factor. This should be derived from the relative OECD Purchasing
Price Parity values for the UK and for Ireland for 2014. The 'PPP' factor is net of currency conversion
(i.e., already includes for exchange rates as well as price differences, and so no currency conversion
rate should be applied in addition to this factor)
- Applying an inflation multiplication factor. This should be derived from inflation rates based on the
CPI in Ireland for the period 2014 – 2016
- The above factors derived and used by the Consultant shall be described in the report.
Flood Duration
The damages should be calculated assuming long duration flooding for residential properties, except
where shorter duration flooding (including the time required for the draining away of flood waters)
would clearly be expected, e.g., in small, flashy catchments, where the short duration damages should
be applied instead.
If it is appropriate, based on the guidance in FHRC to assume extra-long duration flooding for residential
properties, then the extra-long duration flooding data shall be used. In all cases, the rationale used by
the consultant in deciding on the appropriate duration data to be used shall be described in the report,
for review.
Coastal Flooding
The data in FHRC 2014 for saltwater flooding shall be used as appropriate for coastal flooding.
D3.2 Scope of Assessment
The calculation of flood damages should be undertaken for:
Each of the Study Areas
The current scenario for flood events with Annual Exceedance Probabilities (AEPs) of 50%, 20%, 10%,
5%, 2%, 1%, 0.5%, & 0.1%
The MRFS and HEFS.
D3.3 Residential Property Damages
Residential Property Classifications
For the purposes of determining the appropriate residential property damages, and the depth-damage
curve / data to be used, account should be taken of:
Property type (detached, semi-detached, terraced, bungalow, etc.)
but not:
Property age
Social class (and without inclusion of the Distributional Impact Factor)
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Property size
The use of properties marked as 'unknown' in the GeoDirectory can be confirmed through the site visits
and/or by remote data such as Google Street Map
Property Floor Levels and Flood Depths
Residential property floor levels (which is the base-line or zero-depth for the calculation of flood
damages) may be determined, subject to confirmation by the Consultant through on-site spot-checks,
on the basis that doorstep / floor levels of ground-floor properties are a specific height above ground
level, which is determined from the DTM data. The specific height of the doorstep / floor level adopted
for the Study Area should be based on observation / measurement of properties in the Study Area.
Flood damages should be assumed to begin at flood depths of –0.3m relative to floor levels. This only
applies however to properties whose foot-print lies within the flooded area, and does not need to be
calculated for properties that are situated outside of the flood extents for the given event.
D3.4
Non-Residential Property Damages
Non-Residential Property Classifications
The Indicative Susceptibility depth-damage curve / data should be used, unless there is a clear and
specific reason to use the High or Low Susceptibility Band data for a given property.
For the purposes of determining the appropriate non-residential property damages, and the depth-
damage curve / data to be used, account should be taken of:
Property type (i.e., each type with a three-digit ‘New MCM Code’, as referred to in FHRC 2014)
Property area
Property Floor Levels and Flood Depths
Non-residential property floor levels may generally be determined, subject to confirmation by the
Consultant through spot-checks and the exceptions as set out below, that doorstep / floor levels of
ground-floor properties are a specific height above ground level as determined from the DTM data. The
specific height adopted for each Study Area should be based on observation / measurement for the Area.
Surveys of the threshold levels for flooding of major commercial properties (those with estimated
potential damages equal to or greater than €500,000 for an event of annual exceedance probability of
0.1% in the Study Area), and also for entry points to significant basements or underground car-parks, are
however required, and these levels where captured should be used.
Flood damages should be assumed to begin at flood depths of 0m. For mixed-use properties, i.e., where
the property includes both residential and (non-residential) commercial use, it could be assumed (unless
otherwise verified through site visit / remote data) that the ground floor will typically be in non-
residential (commercial) use, and so the non-residential approach should be applied, i.e., assume flood
damages begin at 0m rather than -0.3m. For converted properties that are now non-residential, the non-
residential approach should be applied.
South Galway - Gort Lowlands Flood Relief Scheme
The ‘with basements’ or ‘without basements’ depth-damage data for non-residential properties should
be used as appropriate. Where the existence or otherwise of a basement is unknown for a given
property, then the ‘without basement’ depth-damage data should be used.
In line with good practice, a ‘reality-check’ should be undertaken for any property that contributes more
than 1% of the total PV damages for a Study Area.
D3.5
Other Damage Costs
Principal Direct Damage (PDD) Costs
The PDD Costs are calculated as the sum of the residential and non-residential property damages. The
PDD Cost is used as the baseline for the calculation of other damage costs, as set out below.
Infrastructural Utility Assets
Economic damages to infrastructural utility assets (e.g., electrical sub-stations, gas installations and pipe-
work, telecommunications assets, etc.) should be calculated as 20% of total PDD Costs for the Study
Area.
(Note: 20% value has been derived from the analysis of damages of past floods in the UK).
Infrastructural Utility Damage Costs should be included for the economic CBA, but should not be included
in the appraisal against Objective 2.a under the MCA.
Emergency Services
Costs to emergency services (which include evacuation costs) should be included in the economic
damages, and should be calculated as 8.1% of the total PDD Costs for the Study Area.
(Note: 8.1% value derived as average of the measured emergency services costs for the 2000 and 2007
floods in the UK).
Traffic Disruption
Costs of traffic disruption may typically be excluded from the calculation of the economic damages, as it
will typically not be significant within the overall damages. This would be, for example, where the
flooding would be of minor roads or local urban streets and where alternative local routes are available
and/or traffic volumes will not be high. Traffic disruption costs may however be included where there
are major (high volume) roads affected and / or where deviation routes are of significant distance.
The inclusion or otherwise of traffic disruption costs is at the discretion of the Consultants, subject to
advice from the Steering / Progress Group.
South Galway - Gort Lowlands Flood Relief Scheme
In the event that traffic disruption costs are calculated, then such damages / costs should be included
for the economic CBA, but should not be included in the appraisal against Objective 2.a under the MCA.
Risk to Life
While clearly of significant importance in the overall appraisal under the MCA, the potential damage
costs of loss of life in a flood event are not to be included in the assessment of economic damages.
(Note: This is excluded because, while loss of life can occur in flood events, in Ireland loss of life due to
flooding is very rare. As such, it would not materially change the economic analysis.)
Where risk to life is of potentially significant concern (e.g., where there is a prevalence of basements and
/ or by observation of the flood hazard (risk to life) mapping and the location of residential / high
vulnerability properties), this should be noted in the description of flood risk for the Study Area, and can
be taken into account in option selection and justification.
Other Excluded Damage Costs
Damage costs can arise in relation to various other types of damage, impacts or costs arising in the event
of a flood. However, these are either not economic losses (i.e., to the overall national economy), are
provided for under another included cost, and / or are typically relatively small as a percentage of the
overall damage and hence do not need to be considered in the economic appraisal at this strategic level
of assessment.
Such excluded costs would include:
Damage to roads
Damage to parked cars
Environmental damage
Personal evacuation costs
Temporary accommodation
Extra heating costs
Losses to businesses
Recreational losses
Many of the above costs are deemed to be included within the Intangible and Indirect Damages (see
Item D3.6 below).
D3.6
Intangible and Indirect Damages
South Galway - Gort Lowlands Flood Relief Scheme
Flood events can cause significant stress, anxiety and ill health to potentially affected people, during and
then after a flood. Individuals generally also incur some costs due to their properties flooding that are
not directly related to damage, such as evacuation, temporary accommodation, loss of earnings,
increased travel and shopping costs, etc.
While these negative impacts are difficult to monetarise or quantify, it is recognised that these impacts
are significant, and professional opinion (Chatterton, pers. comm) has indicated that they could well be
greater than the direct damages to residential properties.
For residential properties, the intangible and indirect flood damages shall together be set equal to the
total (direct) property damage.
Intangible damages shall also be applied in the case of individually or family-owned small businesses
where the intangible impact would be personal and similar in nature to that which might be experienced
were the property residential. The inclusion of intangible damages for non-residential properties shall
however be justified on a property-by-property basis, and may not be generally applied across an entire
sector or sub-sector.
While recognising that there will be some impact to those living above ground floor level (e.g., in
apartment buildings), the intangible impact will, in line with the economic damages, be quite limited
relative to those in properties that are flooded.
Intangible and indirect damages should be included for the economic CBA, but should not be included in
the appraisal against Objective 2.a under the MCA (as they are provided for under other MCA objectives).
D3.7 Calculation of Annual Average Damage
The Annual Average Damage (AAD) shall be calculated using linear interpolation between damage values
for each of the eight defined design event probabilities, i.e., with a damage value calculated for each
‘slice’ based on the average of the damages for the design event damages that form the probability
boundaries for the ‘slice’, and the probability range of the ‘slice’.
The AAD is calculated as the sum of the damage values of each slice, up to and including the ‘slice’ with
the 0.1% AEP event as the upper bounding event.
D3.8 Calculation of the Present Value of Damages (PVd)
The PVd should be calculated as the discounted sum of the annual average damages over the project
horizon, where:
- - The discount rate to be applied is 4%
- - The project horizon is 50 years
South Galway - Gort Lowlands Flood Relief Scheme
The discount rate is subject to sensitivity testing, see Section D5.1
D4.0 CALCULATION OF ECONOMIC BENEFITS OF FLOOD RISK MANAGEMENT OPTIONS
D4.1 General Requirements
The economic benefits of an option for a flood risk management measure, or of a proposed flood risk
management measure, are calculated as the reduction in the economic damages the option or measure
will provide. The benefits / damages should be calculated assuming protection to the defined / proposed
Standard of Protection (SoP), i.e., not taking into account freeboard / factor of safety.
Baseline Scenario
The baseline scenario against which benefits of an option or measure should be compared is the current
situation or ‘continue with existing practice’ in terms of arterial drainage maintenance, local authority
maintenance regimes for urban channels, culvert inlets, etc.
(Note: This is different from the usual ‘Do Nothing’ baseline scenario against which benefits of further
action, or maintaining the status quo, are measured. This is necessary due to the nature of current
activities, and the uncertainty associated with damages that would arise should those activities cease).
Defence Options or Measures
For options or measures involving direct flood defence of an area, such as a wall or embankment, the
reduction in damages should be calculated as the damages avoided to up and including the standard of
protection of the option or measure, with no benefit offered for events greater than standard of
protection.
(Note: This approach will tend to under-estimate the benefits of an option or measure, as it ignores the
residual benefits for greater-than-design events. However, these residual benefits would be offset to
some degree by increased damages that could arise in the event of the failure of the defence, and the
above approach simplifies that analysis required.)
Other Flood Hazard Reduction Options or Measures
For options or measures that involve reducing flood flows or levels through the relevant area, such as
flood water retention or increasing in-bank channel capacity, the reduction in damages will need to be
calculated by running the model for the flood event probabilities for which flooding and damage will
occur to determine the flood damages for those events, and hence the reduction in damages from the
current scenario. The event of probability equal to the standard of protection, or for which no flooding
or damages would arise, will also need to be run to demonstrate the effectiveness of the option or
measure at the intended ‘zero-damage’ event probability.
D4.2 Present Value of Benefits (PVb)
The PVb of an option or measure is the reduction in the Present Value of damages (PVd) that would be
avoided by implementing the option or measure (where the PVd is calculated as set out in Section D3.8
herein based on the discount rate and the project horizon), but also taking into account the capping of
benefits as set out in Section D4.3 below.
D4.3 Property Value Capping
South Galway - Gort Lowlands Flood Relief Scheme
The costs of a measure or scheme (i.e., an option) with respect to a particular property should not exceed
the total value of that property and, where relevant, the intangible damages that can be avoided through
relocation; otherwise the State could end up investing more in protecting an asset than the value of that
asset and associated intangible consequences, and a lower cost alternative measure (relocation) could
be implemented instead. Capping values are hence applied to PVb of an option when undertaking an
economic CBA.
Capping should not be applied to the property damages for the appraisal against Objective 2.a under the
MCA nor for the economic damage risk maps, as these should reflect the 'Do Nothing' or current
situation.
Residential Property Value Capping
The capping value of the Principal Direct Damages (PDD) for a residential property is based on the value
of that property. The value for a given property can be based on local or regional valuations of that type
of property, i.e., a property-specific valuation is not required. Information on residential property prices
is available from a number of publicly available sources (e.g., Residential Property Price Register, Daft.ie,
etc.) and shall be obtained by the Consultant.
The total capping value should however also take into account the PVd related to the intangible damages
for a property, noting that these can be ongoing and not only the direct consequences of a given flood.
The PVb capping value for intangible benefits of an option should be set equal to the capping value for
the PDD for the property, representing the intangible damages avoided over the project horizon if the
property (and it's residents) were to be relocated, but taking into account the capping of the PDD of the
property.
The Total Capping Value for the PVb for a residential property is therefore calculated as the sum of the
capping value for the PDD for a property and the capping value of the intangible damages for that
property. As the latter is equal to the former, this value is effectively double the capping value for the
PDD of a property (i.e., double the property value).
Non-Residential Property Value Capping
The capping value for the PVb for a given non-residential property can be derived from regional
valuations of that type of property, taking account of typical stock, or as ten (10) times the current
rateable value of the property.
The information required on regional valuations of property type for this purpose shall be obtained by
the Consultant and described in the report for review.
Capping of Other Damages
Capping should be applied to property damages and intangible damages only. Capping should not be
applied to damages calculated as a percentage of the Principal Direct Damages (PDD), such as emergency
services costs.
South Galway - Gort Lowlands Flood Relief Scheme
D4.4 Exclusions from Benefit Calculations
Potential increases in property value (including land value) arising from the implementation of a scheme
may not be counted as scheme benefits.
D4.5 Reduction in Risk (Benefits) for Appraisal against MCA Objective 2.a
The economic benefits used for the economic cost-benefit analysis (CBA) to determine the benefit-cost
ratio should be as set out above.
The economic benefits used for the appraisal of options or measures under the MCA against Objective
2.a (Minimise Economic Risk) are as set out above, but should not be capped (Section D4.3) and with
certain exclusions as referred to above, including:
Benefits to infrastructural utilities (Section D3.5)
Benefits in reduction of disruption to traffic (Section D3.5)
Intangible and indirect benefits (Section D3.6)
These exclusions are to avoid double-counting benefits within the MCA.
D5.0 COST – BENEFIT ANALYSIS
D5.1 General Methodology
The benefit-cost ratio (BCR) to be produced as the output of the cost-benefit analysis is calculated for
each option or measure by dividing the PVb for an option or measure, capped as appropriate, by the
whole life cost (PVc) of that option or measure.
The Net Present Value of the benefits (NPVb) of the option should also be calculated by deducting the
PVc from the capped PVb.
Guidance on deriving costs for options or measures is provided under the guidance on the use of the
OPW Unit Cost Database. The whole life cost is determined from the sum of the costs over the project
horizon, with future costs discounted by the set discount rate (see Section D3.8 herein). However, the
Consultant should estimate costs for options or measures using data that they have to hand relating to
costs of similar works completed in their work areas, if such data is more suitable or appropriate than
the OPW Unit Cost Database.
It should be noted that it is expected that the Estimated Cost prepared for the CBR estimation in Stage
II of the project should be the basis of the Estimate of Cost to be prepared for Stage III of the project.
It should be noted that residual asset values of potential flood risk management measures (i.e., at the
end of the project horizon) should be assumed to be zero.
South Galway - Gort Lowlands Flood Relief Scheme
In addition to the Capital Costs of the works involved in an option or measure the following additional
items shall be added to determine the Project Cost for the option or measure.
Provision for unmeasured items (See Note below)
Provision for optimism bias (See Note below)
Maintenance costs (Discounted NPV of maintenance costs throughout project lifespan, i.e., 50
years) (See Note below)
Detailed Design (Design Fees)
Construction Supervision
Allowances for Archaeological and/or Environmental monitoring / exploration
Cost of Land Acquisition / Compensation
Allowance for Art (Refer to the OPW for current guidelines)
Note: The optimism bias provided for in the OPW Unit Cost Database should be used, unless better
information is available. This includes a provision for unmeasured items. The Unit Cost Database also
provides for the inclusion of operation and maintenance costs and preliminaries.
Allowances for these items shall be based on percentage rates to be advised by OPW or as agreed by the
Steering Group.
Note that VAT and the cost of OPW staff time shall not be included in potential scheme costs for the
purposes of cost – benefit analysis.
Measures are only likely to be recommended as measures to be put forward in the Flood Risk
Management Plan if their BCR is greater than unity.
Sensitivity tests should be undertaken to determine the BCR using higher or lower discount rates, which
should be 5% and 3% respectively.
D6.0 REFERENCES AND RESOURCES
References
a) FHRC 2014: Handbook for Economic Appraisal, Flood Hazard Research Centre (FHRC), Middlesex
University
b) FHRC 2010: The Benefits of Flood and Coastal Risk Management: A Handbook of Assessment
Techniques – 2010, FHRC, Middlesex University
South Galway - Gort Lowlands Flood Relief Scheme
c) FHRC 2005: The Benefits of Flood and Coastal Risk Management: A Manual of Assessment
Techniques, FHRC, Middlesex University
Resources
CFRAM GN28 – Option Appraisal and the Multi-Criteria Analysis Framework
NOTE: GLOSSARY OF ABBREVIATIONS
AAD Annual Average Damages
AEP Annual Exceedance Probability
AFA Area for Further Assessment
BCR Benefit – Cost Ratio (Benefits / Costs)
CBA Cost – Benefit Analysis
CPI Consumer Price Index
DTM Digital Terrain Model
FHRC Flood Hazard Research Centre (Middlesex University, London)
HEFS High End Future Scenario
MCA Multi-Criteria Analysis
MCM Multi-Coloured Manual
MRFS Mid-Range Future Scenario
NPVb Net Present Value of the benefits of a potential Scheme (PVb - PVc)
OECD Organisation of Economic Co-operation and Development
PPD Principal Direct Damages (sum of direct damages to residential and non-residential damages)
PPP Purchasing Power Parity
PVb Net Present Value of Benefits (whole life, discounted benefits)
PVc Net Present Value of Costs (whole life, discounted costs)
PVd Net Present Value of Damages (whole life, discounted damages)
NOTE: EXPLANATORY TABLE
The table below sets out which parameters are applicable for each use (Economic CBA, Economic Risk Mapping and
appraisal against MCA Objective 2.a), and how some of the parameters (e.g., Total damages for a given event, AAD)
are calculated based on previous parameters.
South Galway - Gort Lowlands Flood Relief Scheme
The relevant sections in the Guidance Note are given in parentheses after the comment on application.
Parameter Application
Economic CBA Economic Risk
Mapping
MCA Appraisal:
Objective 2.a
1 Residential Damages Yes (D3.3) Yes (D3.3) Yes (D3.3)
2 Non-Residential Damages Yes (D3.4) Yes (D3.4) Yes (D3.4)
3 Principal Direct Damages (PDD) 1 + 2 1 + 2 1 + 2
4 Intangible Damages Yes (D3.6) Yes (D3.6) No
5 Infrastructural Utility Damages Yes (D3.5) Yes (D3.5) No
6 Emergency Services Yes (D3.5) Yes (D3.5) Yes (D3.5)
7 Traffic Disruption Possibly (D3.5) Possibly (D3.5) No
8 Event Damage 3 + 4 + 5 + 6 + 7 3 + 4 + 5 + 6 + 7 3 + 6
9 Annual Average Damage (AAD) Annualise 8 Annualise 8 Annualise 8
10 Present Value of Damages (PVd) Discounted sum of 9
over Project Horizon N / A
Discounted sum of
9 over Project
Horizon
11 Un-capped PVb
Reduction in PVd (10)
provided by Option
(D4.2)
N / A
Reduction in PVd
(10) provided by
Option (D4.2)
12 Capping Value
Double Residential
Property Value, or, =
Non-residential
Property Value (D4.3)
N / A N / A
13 Capped PVb 11, but not > 12 (D4.3) N / A 11 (D4.3)
14 PVc Whole Life Scheme
Cost N / A
Whole Life Scheme
Cost
15 BCR 13 / 14 (D5.1) N / A 13 / 14 (D5.1)
16 NPVb 13 - 14 (D5.1) N / A 13 - 14 (D5.1)
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APPENDIX E
SCREENING FOR APPROPRIATE ASSESSMENT AND EIAR TECHNICAL
SPECIFICATION
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1 INTRODUCTION
Galway County Council and the Office of Public Works (the ‘OPW’) recognising the significant flood risk that exists
in South Galway- Gort Lowlands as evidenced by floods in the past, most notably in winters 1994/95, 2009, 2014
and 2015/16 are progressing a flood relief scheme for the affected areas and the required studies for adjacent
upstream and downstream areas. The study area is outlined in Figure 1.
Following the major flooding in 1994/95, the OPW commissioned an extensive report on flooding in the South
Galway Area. Jennings O’Donovan produced a report in April 1998 which included an examination of the flooding
problem, hydrological/hydrogeological processes, effects of climate change, environmental concerns/impacts and
an examination of works that could be undertaken to alleviate future flooding. The report included an examination
of a possible engineered overland flood overflow channel between Coole Lough and Kinvarra. A review in 2010 of
the fully engineered channel proposal, estimated the cost of provision at €48m, excluding VAT. The channel proposal
was unviable from a CBA perspective and judged to be unlikely to meet with approval from an ecological perspective.
Following a review of the floods events in 2009, a number of restoration works identified in previous reports were
undertaken. These works sought to restore previous natural flows, where it was felt human intervention had caused
restrictions:
A number of undersized and defective culverts were substantially upgraded to facilitate modelled and
observed flows through adjacent upstream and downstream culverts and bridges.
New culverts were installed on natural flood paths where roads had been raised above natural contours
and insufficient allowance had been made for flood flows.
Minor clearance works have been undertaken around selected swallow holes.
Notwithstanding the works undertaken, the record levels of rainfall that were recorded over a prolonged period in
2015/2016, resulted in Coole turlough flooding to a depth of 1m above the record levels of 2009, equivalent to 20%
volumetric increase in storage within the turlough. This resulted in unprecedented levels of flooding to homes and
lands throughout the Lowland area.
The intensity and duration of rainfall experienced in the six flood events of the last twenty years cannot be routed
through the network of existing subterranean conduits to Galway Bay. The resultant uncontrolled overflow of the
network is a cause of extreme annual concern to the residents and farming communities in the area. A total of 20
households and businesses were flooded in the recent event and an additional 20 households were at serious risk
of flooding with many households reliant on sandbags and an enormous community effort to prevent flooding. In
some cases these efforts extended to weeks.
Further mitigation works on the network have been suspended, as the effect of these works on other areas of this
unique and complex network has not been fully assessed. This project will involve a full examination of all elements
effecting flooding in the area from source to discharge and will determine a programme of works to be undertaken.
The project will take account of all works and measures undertaken to date.
The combination of river water, groundwater, swallow holes and turloughs in the karst Gort Lowlands catchment,
makes this area unique on an international level from an ecology perspective and this is evidenced by the number
of Designated Areas (SACs, SPAs and pNHAs) attributed to the catchment. The complexity of the flow network within
the catchment has justified an ongoing collaborative study between Geological Survey Ireland and University of
Dublin Trinity College which will greatly assist in the formation of the hydrological and hydraulic analysis of the
scheme.
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A specialist environmental consultant will be commissioned by GCC to carry out the environmental aspects of the
Feasibility study. The scope of works to be commissioned (hereafter referred to as the ‘Commission’) is set out
below.
The Design Team shall be made up of personnel from Galway County Council, the OPW and with the addition of
Consultant Engineers on appointment.
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2 SCOPE OF COMMISSION
2.1 STUDY AREA
The principle study area for the Commission is the Gort Lowlands area and its highland catchment. The Lowland
area has widespread groundwater networks and turlough features. The catchment area in the Slieve Aughty’s and
the discharge area of Kinvarra Bay in Galway Bay SAC are also in the commission. The combined areas are situated
in South County Galway and cover a land area of approximately 470 sq.km. with a population of approximately
10,000.
Figure 2: Principle Study Area of Gort Lowlands is Outlined in Black and Includes the Entire Catchment Area. The
Lowland Areas with Predominantly Groundwater Networks are Labelled Kinvarra West (hatched in red) and
Kinvarra East.
The Environmental Consultant is required to identify sensitive habitats or features adjacent to, up and/or down-
stream of the principal study area, which could potentially affect or be affected by the preferred flood relief scheme
option identified within the Feasibility Study. Flow reduction from the extensive upland area will form part of the
engineering consideration (see Section 3.2.1.1).
The areas in and adjacent to the principle study area that suffered flooding in the most recent events are highlighted
in Figure 2.
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Figure 2: Areas Flooded in the 2009 and 2015 Flood Events Shown in Red.
2.2 OVERVIEW OF THE COMMISSION
2.2.1 Stage I - Constraints Study and Screening for Appropriate Assessment
This is divided into two parts:
Part 1 - Constraints Study
Identify the key environmental issues (see figure 3) in the study area, which may be impacted upon by possible flood
alleviation measures, and/or which may impose constraints on the viability and/or design of one or more measures
(see Section 3.1.1).
Part 2 - Screening for Appropriate Assessment
Carry out an initial Appropriate Assessment (AA) Screening statement (see Section 3.1.2).
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Figure 3: Environmental Designations within the Principle Study Area
2.2.2 Stage II – Environmental Assessment of Viable Options and Natura Impact Statement
Part 1 - Environmental Assessment of Viable Options
Review the assessment of the environmental effects of the flood alleviation options that are developed by the
Engineering Consultant upon appointment. This will inform the Design Team in refining or changing the preferred
scheme option (see Section 3.2.1).
Part 2 – Natura Impact Statement
If applicable based on the outcomes from Stage I (Part 2), carry out a Natura Impact Statement (NIS) subject to
recommendations of the initial screening (see Section 3.2.2).
2.2.3 Stage III - Environmental Impact Assessment Report (EIAR)
Prepare an EIAR for the preferred flood relief scheme option (see Section 3.3).
Note: The Environmental Consultant should note the An Bord Pleanála further information requests and responses
to submissions that were associated with the ‘Dunkellin River and Aggard Stream Flood Relief Scheme, October
2014’. The Dunkellin River discharges to the Galway Bay SAC 9km north east of Kinvarra.
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2.2.4 Stage IV - Public Exhibition
Participate in the Public Exhibition, pending the scheme being approved and granted funding to proceed (see Section
3.4).
2.2.5 Additional Work
Specific Detailed Investigation Work – Additional work may be required during Stages I to IV, subject to the review
of the Feasibility Study and approval of the Design Team. Such work might comprise detailed studies, surveys or
advice, which cannot be identified in advance of commencement of the Commission (see Section 3.5).
2.2.6 Pricing of Stage I to Stage IV
The Commission will have four stages (plus possible additional work). Pricing shall be broken down as follows:
Stage I, Stage II (Part 1) shall be one inclusive price.
It is anticipated that Stage I, Stage II (Part 1) and Stage III will follow on from each other but confirmation
before starting each stage must be received from the Office of Public Works.
Stage II (Part 2): Natura Impact Statement is provisional, based on the outcomes from Stage I (Part 2):
Screening for Appropriate Assessment, thus Stage II (Part 2): Natura Impact Statement must be priced
separately.
Confirmation from the Office of Public Works must be received before proceeding with Stage II (Part 2).
Stage III: This will require approval to proceed from Galway County Council and may not be required.
Stage IV: Public Exhibition must be priced separately.
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3 DETAILED SPECIFICATION OF WORK REQUIRED
3.1 CONSTRAINTS STUDY (STAGE I PART 1) AND APPROPRIATE ASSESSMENT SCREENING (STAGE I PART 2)
3.1.1 Constraints Study (Stage I Part 1)
3.1.1.1 Scope
The Environmental Consultant will identify the key environmental issues associated with the Feasibility Study within
the principal study area and the discharge point of Kinvarra Bay. These issues will include, but not necessarily be
limited to:
Flora and fauna
Fisheries
Habitats
Water quality and Hydromorphology
Archaeological, architectural and cultural heritage
Landscape and visual amenity
Angling, tourism and recreational use
Flood-related social or socio-economic issues (but excluding economic flood-damage analysis.)
The Environmental Consultant will undertake a series of desk studies, consultations with all relevant statutory
bodies and the main non-governmental organisations with an interest in the issues, and carry out preliminary site
visits by specialist’s contractors in the relevant disciplines to identify issues that might be relevant to, or impose
constraints on, the design and construction of any flood alleviation measures. It will also include an initial public
consultation including a public information day.
The Environmental Consultant will review previously commissioned reports for areas within the principle study area
and confirm previous findings or progress alternative options if available. Note, ‘Termon North Flood Alleviation
Scheme – Pumped Option, July 2014’. Early and thorough engagement with NPWS will be required for this project.
NPWS have already engaged with local community groups (including South Galway Flood Relief Committee)
regarding turlough levels and flood damage to SAC habitats.
In relation to flora, fauna, fisheries and habitats, the Environmental Consultant shall identify the key species, the
location of important habitats, and the aspects of the species or habitat that could potentially be impacted upon, or
constrain, the design and construction of a flood alleviation scheme. The requirement for salinity modelling in the
‘Dunkellin River and Aggard Stream Flood Relief Scheme EIS, October 2014’, should be noted.
In relation to water quality and hydromorphology, the Environmental Consultant will identify water quality elements
and hydromorphological quality elements that could be impacted upon or act as a constraint on the scheme design.
The archaeological, architectural and cultural heritage aspects of the study shall identify known sites and features
and areas of archaeological and / or heritage importance. For known sites, the study should identify a zone of
avoidance around the site, if relevant.
The landscape study should identify the significant features in the landscape, which determine its character with
particular reference to rivers, flood plains, flood channels, turloughs, springs, swallow holes, estravelles etc. The
GSI’s Karst Database documents all known karst features to date. It should be noted that this is not a comprehensive
record of all existing karst features, and only reflects landforms that have been mapped and recorded to date. To
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improve the existing GSI database and to allow for any future requirements, all karst features encountered during
the course of this project are to be mapped, recorded and forwarded to Caoimhe Hickey ([email protected]).
The Environmental Consultant will not be expected to undertake detailed field surveys for specific species under
this Stage, unless requested to do so by the Design Team. If such work is requested, it will be undertaken as
Additional Work (see Section 3.5).
NOTE: The range of flood alleviation measures typically considered as part of the Feasibility study, and which would
need to be considered in relation to possible impacts or constraints are outlined in Section 3.2.
3.1.1.2 Information to be supplied by the Design Team
Digital maps of the area (where available from the Ordnance Survey) will be made available to the Environmental
Consultant, and a briefing provided on the possible engineering measures.
The following reports are attached or where stated will be supplied when available to the appointed Environmental
Consultant;
See Appendix A for list
3.1.1.3 Public Information Day
The Environmental Consultant will prepare for, arrange and manage a Public Information Day and prepare
supporting information. The purpose of the event will be to seek initial views from the public and other interested
parties in relation to the key issues that the study should address, and to highlight points of local importance that
might constrain the design and/or viability of any potential flood alleviation measures. The Environmental
Consultant will agree the date with the Design Team.
The Environmental Consultant, subject to approval from the Design Team, will make any necessary arrangements
for the conduct of this event as considered necessary including, but not limited to, the following;
Organise an appropriate venue/date and make reservations as appropriate. Note that the Environmental
Consultant will not be expected to pay the cost of any reservation.
Prepare advertisements for the event to be provided to the local media (newspapers and local radio). Note
that the Environmental Consultant will not be expected to pay any charges related to the placement of such
advertisement in the media.
Write to local organisations advising them of the event at least one week in advance.
Prepare and print a brief information leaflet (200 copies, normally a folded A3 colour print on high-quality
paper) to be given to visitors to the event, and which might be made available more widely within the
principal study area.
Prepare and print information posters (20 copies, normally an A1 colour print on high-quality paper) to
inform the public of the event.
Prepare and print a simple questionnaire (200 copies, normally an A4 colour print on high-quality paper) to
be issued at the event.
Prepare pre-addressed, Freepost envelopes for the return of questionnaires (200 copies).
Provide a visual display for the event outlining the purpose of the Feasibility study and the event, and
demonstrating the types of measures that are typically used for flood alleviation (Large format posters as
a minimum).
Provide staff to attend the event to assist the public and answer, where possible, any questions arising.
The Environmental Consultant shall compile a summary report of the oral comments received at the event and the
written responses provided on the questionnaire form, which shall be included in the Constraints Report to the
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Design Team. Copies of the questionnaires received shall also be provided to the Design Team by the Environmental
Consultant.
The members of the South Galway Flood Relief Committee have amassed a very broad knowledge of issues that
cover a large proportion of the principle study area. Given the extent of knowledge and the resources that will be
required to manage the interface with the Committee, the Environmental Consultant will meet with the Committee
in advance of the Public Information Day. The views and feedback from this meeting shall be treated as similar to
those received in the Public Information Day and included in the Constraints Report. Following this meeting, the
Environmental Consultant should be better informed with regards to issues and questions that will likely arise in the
course of the Public Information Day.
3.1.1.4 Output from the Constraints Study
The output from the Constraints Study will be a report, including graphics, which will identify the constraints and
issues arising and provide a full account of the findings of the study and Public Information Day, the topics and
geographic areas covered, the documents referred to and the organisations and people consulted. The
Environmental Consultant will also attend a meeting to brief the Design Team on the findings of the study and be
available to answer further queries, if necessary. This briefing shall include the feedback from the Public Information
Day.
The Consultant shall allow for producing 3 hardcopies of the Constraints Study and 2 digital copies shall be provided
(on CD or DVD).
3.1.1.5 Programme for Constraints Study
The report on the study shall be submitted at a suitable time so as not to impact on the progress of Stage II Part 1.
3.1.2 Screening for Appropriate Assessment (Stage I Part 2)
3.1.2.1 Scope and Outputs
Prepare a Stage 1 Screening Statement for an Appropriate Assessment in line with Appropriate Assessment of Plans
and Projects in Ireland – Guidance for Planning Authorities (DoEHLG 2010). This shall identify the conservation
objectives of all relevant Natura 2000 Sites, conservation measures for SAC's and requisite measures for SPA's and
any other measures to prevent disturbance or deterioration of these sites. Consider potential impacts within the
likely zone of impact of the works on any Natura Site conservation aspects either upstream or downstream of the
works location. The Screening Statement shall demonstrate that the likely impacts of the proposed measures on the
relevant Natura 2000 Sites have been examined in the context of the conservation objectives for those sites. The
Screening Statement should conclude with a recommendation on whether a full Appropriate Assessment is required
as outlined in 3.2.
3.1.2.2 Programme for Screening for Appropriate Assessment
A Screening Statement for an Appropriate Assessment shall be submitted at a suitable time so as not to impact on
the progress of Stage II Part 2.
The Environmental Consultant shall allow for producing 3 hard copies of the Screening Statement for Appropriate
Assessment and 2 digital copies of each shall be provided (on CD or DVD).
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3.2 ENVIRONMENTAL ASSESSMENT OF VIABLE OPTIONS (STAGE II PART 1) AND APPROPRIATE ASSESSMENT (STAGE
II PART 2)
3.2.1 Environmental Assessment of Viable Options (Stage II Part 1)
3.2.1.1 Scope
Once the major environmental issues and constraints have been identified (Stage I), the Environmental Consultant
will, for Stage II (Part 1), assess in detail and report upon the environmental impacts associated with each element
of these schemes as set out in the Engineering Reports, and suggest mitigation measures, where feasible.
One engineering measure, or a combination of locally effective engineering measures can form the basis of solutions
that provide protection against flooding for flows up to the design standard; one of these solutions may become the
final, preferred flood relief scheme.
The range of engineering measures typically considered in viable options for possible flood alleviation schemes in a
Feasibility study and which may need to be considered in relation to possible impacts or constraints include, but are
not limited to, the following:
(a) Do Nothing (i.e., implement no new flood alleviation measures)
(b) Non-Structural Measures
Installation of a flood warning system
Individual property protection
Restrictions on development in the Flood Plain in line with Planning guidelines on Flood Risk Management
and the Planning System
(c) Relocation of Properties and/or infrastructure
(d) Reconstruction of Properties and/or infrastructure to a higher level
(e) Flow Diversion
Diversion of entire river
Flood flow bypass channel
(f) Flow Reduction
Upstream catchment management (i.e. reduce runoff)
Upstream flood storage (single site or multiple sites)
(g) Flood Containment through Construction of Flood Defences
Walls or embankments
Demountable defences
(h) Increase Conveyance (upstream and / or through and / or downstream of the town)
Change the channel section and / or grade
Change the floodplain section and / or grade
Remove or reduce local key constraints, e.g. bridges, bends, throttles, infill material on a floodplain, etc.
Reduce the roughness of the channel / floodplain (removal of vegetation, lining, etc.)
Specify ongoing channel / floodplain maintenance
(i) Sediment Deposition and Possible Sediment Traps
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(j) Tidal Barrage
(k) Pump storm waters from behind flood defences
(l) Measures Specific to the Study Location
3.2.1.2 Information to be supplied by the Design Team
The Design Team will provide maps and outline drawings that will show the location and main features of the
schemes. The Environmental Consultant will attend a meeting with the Design Team at which the scheme options
will be explained. Any additional information required by the Environmental Consultant will be identified and
provided at the meeting or shortly afterwards.
3.2.1.3 Output from the Environmental Assessment of Viable Options
The output from this study will be a report that will identify the likely environmental impacts of each scheme. The
impacts should be described in terms of quality, significance, duration and type, as defined in the Glossary of Impacts
in the Guidelines on the Information to be contained in Environmental Impact Statements, published by the EPA,
2002. The report will not identify a preferred scheme or ranking of schemes.
Mitigation measures and environmental enhancement measures that could be incorporated into the schemes
should also be suggested. If there is some reason why it is not possible to assess the impacts of any scheme or
element of a scheme, this fact should be brought to the attention of the Design Team as soon as reasonably
practicable.
The ‘Do Nothing’ option is to be assessed whereby the present impacts of periodic flooding are likely to continue.
The damage to building materials and finishes below the peak flood level and other forms of disruption arising from
an ongoing risk of flooding shall be documented.
The findings of the study shall be presented to the Design Team at a meeting.
The Environmental Consultant shall allow for producing 3 hardcopies of the report and 2 digital copies shall be
provided (on CD or DVD).
3.2.1.4 Programme for the Environmental Assessment of Viable Options
The assessment report of the alleviation schemes shall be completed within one month of the Environmental
Consultant receiving the information on the viable options from the Feasibility study.
3.2.2 Natura Impact Statement (Stage II Part 2)
The Natura Impact Statement (NIS) is subject to 3.1.2 recommendations and approval granted to proceed.
3.2.2.1 Scope
Subject to the results of the Screening for Appropriate Assessment, the Environmental Consultant shall undertake a
detailed NIS, based on best scientific knowledge, to assess the impacts of the preferred flood relief scheme measures
on identified Natura 2000 sites in the context of the conservation objectives of those sites. Field evaluations shall
be conducted as necessary to inform an Appropriate Assessment based on the conservation objectives of the
designated site as well as any additional features deemed pertinent to the assessment. The NIS should detail the
methodologies applied in assessing impacts, proposing mitigation measures and in reaching conclusions. The NIS
should be produced in line with the guidelines as set out in Appropriate Assessment of Plans and Projects in Ireland
- Guidance for Planning Authorities (DoEHLG, 2010) and be prepared by a competent person or persons as required
by this guidance.
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3.2.2.2 Output
Specifically, the Environmental Consultant shall be required to carry out the following:
Produce the Natura Impact Statement which assesses the preferred schemes and prescribes mitigation and
environmental improvement measures as necessary to bring the preferred flood relief scheme to the conclusion
that the project will not adversely affect the integrity of any Natura 2000 site, either alone or in combination with
any other plans or projects.
Draft the AA Conclusion Statement and forward same to Galway County Council.
Prepare AA Screenings for required Site Investigation works at this time, to be undertaken as Additional Work (See
section 3.5)
3.2.2.3 Consultation
It is recommended that consultation with NPWS and the Department of Communication, Climate Action and
Environment (D/CCAE) takes place before finalising the process.
3.2.2.4 Monitoring
While there is no explicit requirement for the ongoing monitoring of the impact of the implementation of projects
on Natura 2000 sites under the Habitats Directive, stemming from requirements set within the NIS, the
Environmental Consultant shall devise the monitoring programme to allow for the assessment of the impact of the
preferred engineering flood relief scheme option on identified Natura 2000 sites.
3.2.2.5 Production of the Statement for Natura Impact Statement and Draft AA Conclusion Statement
The Environmental Consultant shall allow for producing 3 hardcopies of the Natura Impact Statement and 2 digital
copies (on CD or DVD). A digital copy of the draft AA Conclusion Statement is to be provided.
3.2.2.6 Update of NIS
Following the public exhibition of the Scheme, where submissions or observations are made which are relevant to
the NIS, it may be necessary to produce supplementary information to compliment the NIS. The Environmental
Consultant shall be responsible for identifying and undertaking any such supplementary information.
3.2.2.7 Programme for the Natura Impact Statement and Draft AA Conclusion Statement
If commissioned, the Natura Impact Statement and draft AA Conclusion Statement shall be submitted at a suitable
time so as not to impact the progress of the project.
3.3 ENVIRONMENTAL IMPACT ASSESSMENT REPORT (STAGE III)
3.3.1 Scope
Within Stage III the appointed Environmental Consultant shall prepare an EIAR, including a Non-Technical Summary,
for the preferred scheme option. The EIAR shall be prepared to meet the requirements of the EIA Directive
2014/52/EU and the Arterial Drainage Acts 1945 and 1995 as amended.
The EPA Guidelines on the Information to be contained in Environmental Impact Statements (EPA 2002) should be
followed but the EIAR should be tailored for the specific circumstances of this project and to legislative requirements
since 2002.
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The EPA has also produced Advice Notes On Current Practice In The Preparation Of EISs (EPA 2003). The project will
be type 12 in the Advice Notes. The Environmental Consultant shall have regard to the advice notes in determining
the topics to be addressed in the preparation of the EIAR.
However, the Advice Notes may contain less emphasis on a number of issues including sustainability, waste
management, architectural heritage, climate change, natural resources, biodiversity, human health and disaster
prevention. The EIAR should contain the information as set out in EIA Directive 2014/52/EU. In tailoring the EIAR to
the specific circumstances of this project the handling, potential reuse, or disposal of spoil excavated or dredged in
the course of engineering works will also have to be addressed. In addition, measures proposed under the Water
Framework Directive should be taken into account in assessing the likely impacts of the proposed measures with
particular regard to the hydromorphology. The EIAR is to be prepared by competent experts and a Non-Technical
Summary shall be produced that will meet the statutory obligations. However, it will also be an important source
of information on the preferred scheme for the general public and shall therefore be prepared with particular
attention given to ease of use, clarity, and high quality graphics.
3.3.2 Consultation
In the preparation of the EIAR, the Environmental Consultant should consult with all relevant statutory and non-
governmental organisations. In addition, a second Public Information Day will be held at this stage to gather views
about the preferred scheme option in advance of the formal exhibition stage. The scope of this day will be as for the
initial Public Information Day, as described in Section 3.1.1.3.
3.3.3 Information to be supplied by the Design Team prior to Start of EIAR
The Design Team will provide the following information (where appropriate) to the Environmental Consultant
A written summary of the methods and findings of the hydrological modelling study, using terminology
accessible to the non-specialist;
A written summary of the alternatives considered and the process of selecting the preferred scheme option;
A written description of the preferred scheme option and a qualitative description of the resulting physical
effect on the overland flood routes;
Any likely hydrological and/or hydraulic effects downstream of the study area;
Outline engineering drawings of the scheme and structures;
A brief description of the anticipated construction methods and sequence;
Indication of construction programme, time of year and working hours;
Cost estimate;
Estimate of the numbers of employees during construction;
Estimate of construction related traffic;
Quantities of excavated or dredged material and disposal of spoil, quantity of material to create
embankments and source of the material;
Geotechnical investigation information
The information will be available in digital and paper format as appropriate. The Design Team will meet the
Environmental Consultant, present the preferred scheme and be available to answer queries.
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3.3.4 Production of the EIAR
The Environmental Consultant should allow for producing 3 copies of the EIAR and 20 copies of the Non-Technical
Summary, bound separately. Note that the Non-Technical Summary may be included in the main EIAR document,
but must also be produced as a stand-alone document. Both the EIAR and the Non-Technical Summary shall be
provided to Galway County Council in digital as well as hardcopy format and the Environmental Consultant will be
required to provide 50 copies in CD / DVD format.
3.3.5 Programme for the EIAR
The Environmental Consultant will be expected to prepare the EIAR and provide draft copies of the EIAR and Non-
Technical Summary for comment within 3 months from receipt of the required information and approval to proceed.
3.3.6 Monitoring
Stemming from the requirements set out in the EIAR, the Environmental Consultant shall devise the monitoring
programme for the monitoring of significant adverse effects on the environment, having regard to the nature,
location and size of the scheme, the significance if its effect on the environment and the use of existing monitoring
being conducted under other requirements.
3.3.7 Update of EIAR
Following the public exhibition of the scheme, where submissions of observations are made which are relevant to
the EIAR, it may be necessary to produce supplementary information to compliment the EIAR. The Environmental
Consultant shall be responsible for identifying and undertaking any such supplementary information.
On completion of the public exhibition and any supplementary information to the EIAR, Department of Public
Expenditure and Reform (D/PER) in carrying out the EIA will review the EIAR. Following this review, it may be
necessary to issue further information if requested by D/PER and the Environmental Consultant shall be responsible
for undertaking any such further information.
3.4 PUBLIC EXHIBITION (STAGE IV)
Pending a preferred scheme option being approved and granted to proceed, the Environmental Consultant will
participate in two presentations, at which the preferred option will be presented to officials from the Office of Public
Works and to officials and elected members of the relevant Local Authorities.
In accordance with the Arterial Drainage Act 1945 and 1995, the preferred option will be presented to the public at
a Public Exhibition to be held in a pre-selected public location in the local area, which will last between 2 and 4
weeks. The Environmental Consultant will prepare large format displays for the Public Exhibition and text and
graphics to be included in a brochure, which will be available to visitors to the exhibition. The displays, graphics, and
text for the brochure shall illustrate, in non-technical terms, the main environmental features in the overland flood
relief route and the main environmental impacts and mitigation measures of the scheme.
The Environmental Consultant may be required to prepare a photomontage and/or artists impressions illustrating
the impact of the preferred option post-implementation. The need and scope for this work cannot be identified at
this time, but rates for the preparation of a photomontage and of an artist’s impression shall be separately and
clearly identified and provided with the tender for Stage IV of this study.
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The Environmental Consultant will provide a staff member, who has been closely involved with the Commission, to
be present for at least 4 separate (and possibly non-consecutive) days during the Public Exhibition to answer queries
from the public. The dates of these days will be agreed with the Design Team and Local Authority.
All display material shall be provided to Galway County Council in digital as well as hardcopy format to enable
reproduction as required.
Responses shall be drafted to submissions made during the Exhibition which are environmentally related.
3.4.1 Programme for Public Exhibition
The Public Exhibition is expected to take place on approval of the refined preferred scheme option.
3.5 ADDITIONAL WORK
If a potential constraint is identified, this might give rise to the need for further detailed field studies or surveys, or
specialist advice that would be outside of the scope of Stages I to IV as defined above. Such work, which would be
necessary for the progress and completeness of either the Feasibility study or the Commission, might include
detailed species surveys, underwater ecological or archaeological surveys, exploratory excavations, etc. The
Environmental Consultant will identify, with appropriate justification, any such work during each Stage of the
Commission.
The scope, programme, etc. for this work cannot be identified in advance of commencement of the Commission,
but day rates for such additional works that might be foreseen shall be separately and clearly identified in the tender
(to include AA for required Site Investigation works). The rates for such works are to be listed under Additional Work,
and shall be applicable for the duration of the Commission.
Any additional work which is likely to cost more than €25,000 shall be subject to an open tender competition at the
discretion of GCC. This would relate to specialist services (e.g. underwater archaeology etc.).
The Environmental Consultant shall be responsible for managing all aspects of any Additional Works, including works
that are undertaken by specialist sub-contractors.
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APPENDIX F
PUBLIC AND STAKEHOLDER CONSULTATION
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F1 STAKEHOLDERS
A number of statutory, non-statutory and local organisations, potentially affected landowners and members of the
general public have been identified as stakeholders in the development and implementation of the Scheme and other
measures under the Project. Listed below is a non-exhaustive list of possible organisational stakeholders. The Consultant
shall identify any further relevant stakeholders.
1.Environmental Authorities
Environmental Protection Agency – Regional Inspectorate
Department of Communications, Climate Action & Environment
Department of Agriculture, Food and the Marine
Department of Arts, Heritage, and the Gaeltacht
Department of Rural and Community Development
Department of the Housing, Planning & Local Government
2. Primary Stakeholders
Office of Public Works
Regional Authorities
County Councils
Town Councils
National Parks and Wildlife Service
Transport Infrastructure Ireland
3. Secondary Stakeholders
An Taisce
Angling and Boating, Clubs or Associations
Birdwatch Ireland
Chambers of Commerce
Coastal Marine Resources Centre
Coillte (Forest Service)
County Developments Boards
Cuan Beo – South Galway Bay Group
ESB – Electricity Supply Board (windfarms)
Fáilte Ireland
Geological Survey Ireland
Heritage Council
Iarnród Éireann
Inland Fisheries Ireland
Irish Creamery Milk Suppliers Association (ICMSA)
Irish Farmers Association
Irish Wind Energy Association
Landscape Alliance Ireland
Marine Institute – Foras na Mara
River Basin District Authorities and Competent Authorities for Water Framework Directive
Sea Fisheries Protection Authority
South Galway Flood Relief Committee
Teagasc
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F2 COMMUNICATIONS PLAN
F2.1 Communications Plan
The consultant shall, within four (4) weeks of Commencement, develop a Communications Plan for the Project as a
whole. This Plan shall identify:
(vii) All relevant stakeholders / organisations and the relevant contact persons in each.
(viii) A programme for publicising the project and disseminating project outputs and information. This programme shall include use of local newspapers, local radio stations, the internet services of both the OPW and participating Local Authorities, local information opportunities and any other media or mechanisms as appropriate and necessary. This will include the creation and use of a Project Website.
(ix) A procedure for Public Consultation, including Stakeholders Workshops, to encourage and facilitate feedback from, and engagement of, members of the public and relevant stakeholders.
(x) Appropriate coordination mechanisms with the implementation of the Water Framework Directive
(xi) A procedure for recording and acknowledging feedback from all members of the public and relevant stakeholders.
The Consultant shall submit the Communications Plan to the Steering Group for review and approval. After approval,
the Consultant shall implement, monitor and update the Plan throughout the duration of the Project.
F2.2 Response to Public Enquiries
Throughout the duration of the Project, the Consultant shall record and promptly respond to any enquiries, comments,
feedback or other correspondence from members of the public or other stakeholders related to the Project. The
Consultant shall be identified in relevant publicity material as the primary point of contact for the Project. For all queries
received from the media or politicians, the Consultant shall prepare an appropriate draft response and forward same
to Galway County Council for review and issue.
F2.3 Project Presentations
The Consultant shall make presentations on the Project, to stakeholder groups, professional seminars or conferences,
public meetings, or other such events, as required throughout the duration of the Project.
F3 PUBLIC INFORMATION AND CONSULTATION
The Consultant shall deliver the services required herein related to public information and consultation in line with the
requirements of Arterial Drainage Acts.
The Consultant shall assist the environmental consultant with the preparation for a Public Consultation Day to present
and receive comment on the preferred Scheme. This assistance shall include the preparation and provision of
information, drawings and other material by the Consultant as necessary.
The Consultant shall provide not less than two appropriately senior staff, including the project manager, who have been
closely involved with the Project to attend the Public Consultation Day and respond to questions arising from the public
and stakeholders. The Consultant shall also present the preferred Scheme to Councillors (which may be immediately in
advance of the opening of the Public Consultation Day to the public).
The Consultant shall receive and register relevant details of all queries related to the Project; either by email, post, via
the website or by other means. All responses shall also be added to the register of queries. The Consultant shall meet
with interested parties as necessary, which may include meetings outside of normal office hours.
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APPENDIX G
FLOOD MANAGEMENT METHODS
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G1 Flood Management Methods
A flood risk management strategy option (‘option’) consists of one or, more commonly, a combination of flood risk
management methods, which might include, but shall not be limited to the following:
Do Nothing (i.e., implement no new flood risk management measures and abandon any existing practices)
Existing Regime (continue with any existing flood risk management practices, such as reactive maintenance)
Do Minimum (i.e., implement additional minimal measures to reduce the flood risk in specific problem areas
without introducing a comprehensive strategy)
Non-Structural Measures (Existing and / or Potential Future Risk)
Planning and development control measures (zoning of land for flood risk-appropriate development,
prevention of inappropriate incremental development, review of existing Local Authority policies in relation
to planning and development and of inter-jurisdictional co-operation within the catchment, etc.)
Building regulations (regulations relating to floor levels, flood-proofing, flood-resilience, sustainable
drainage systems, prevention of reconstruction or redevelopment in flood-risk areas, etc.)
Sustainable urban drainage systems
Installation of a flood forecasting and warning system and development of emergency flood response
procedures
Targeted public awareness and preparedness campaign
Individual property flood resistance (protection / flood-proofing) and resilience
Land use management, including creation of wetlands, riparian buffer zones, etc.
Structural Measures (Potential Future Risk)
• Strategic development management for necessary floodplain development (pro-active integration of structural measures into development designs and zoning, regulation on developer-funded communal retention, drainage and / or protection systems, etc.)
Structural Measures (Existing Risk)
Storage (single or multiple site flood water storage, flood retardation, etc.)
Flow diversion (full diversion / bypass channel, flood relief channel, etc.)
Increase conveyance (in-channel works, floodplain earthworks, removal of constraints / constrictions,
channel / floodplain clearance, etc.)
Construct flood defences (walls, embankments, demountable defences, etc.)
Rehabilitate, improve existing defences
Relocation of properties
Localised protection works (e.g., minor raising of existing defences / levels, infilling gaps in defences, etc.)
Channel or Flood Defence Maintenance Works / Programme
Other works that might be of particular relevance to, or suitability for, a given location
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APPENDIX H
SCHEME DOCUMENTATION
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SCHEME DOCUMENTS:
The objective of the scheme documentation is to inform by describing in detail the works proposed to be carried out
under the scheme and to enable the general public without any training in the reading of specialist maps, drawings, or
other documents to clearly comprehend the works proposed under the scheme and more particularly insofar as these
works affect individual landowners and the local community. The importance of getting the documents correct cannot
be overemphasised as the statutory authority to execute the scheme works is based on these documents.
Scheme documents comprise of:
(a) Schedules outlining in detail the drainage and other works proposed to be carried out under the scheme;
the names of the reputed proprietors, owners and rated or other occupiers of the lands proposed to be interfered
with under the scheme.
(b) Maps outlining the waters and watercourses to be dealt with; the lands to be drained or otherwise improved by
the scheme; lands proposed to be compulsorily acquired or substantially interfered with under the scheme.
(c) Drawings/Plans/Sections outlining details of the designed works proposed to be carried out under the scheme.
(d) Environment Impact Assessment Report (EIAR) An Environmental Impact Assessment Report, including a Non-
Technical Summary is required for the preferred scheme option. The EIAR shall be prepared to meet the
requirements of the EIA Directive 2014/52/EU and the Arterial Drainage Acts 1945 and 1995 as amended (The EIAR
to be supplied by the Environmental Consultants).
(e) Interference Notices which issue to each reputed proprietor, owner and rated or other occupier and/or the
beneficiaries of a right of way, fishing right or other similar right detailing the extent of works proposed to be carried
out under the scheme on their respective lands/property. For the purposes of this tender assume that 100 notices
will issue.
SCHEME SCHEDULES:
Scheme Schedules (usually A4 Landscape format) are divided into four segments
(a) Preamble - detailing the general objectives of the scheme and outlining the keys to the colours used in the scheme
documents, etc. The wording of the Preamble is fairly standard for all schemes and will be supplied by the
Commissioners.
(b) Schedule A - outlines in general detail the works proposed to be carried out under the scheme in various areas.
(c) Schedule B - outlines in specific detail the works proposed to be carried out on individual landowners’ properties
and includes all aspects of the works envisaged or likely to arise as a consequence of the scheme interferences. This
schedule also includes the names and addresses of owners, occupiers, etc.
(d) Schedule C - outlines the aggregate annual value of the benefited lands and the total increase in the annual value
of the benefited lands which will probably arise as a consequence of the execution of the scheme (this is specialist
information which will be supplied by the Commissioners), but existing flood extent maps will be required for the
2, 5, 10, 20, 50 and 100 year events from the Consultant.
MAPS:
Since the main objective of the scheme documentation is to inform the public as to the type and extent of the works to
be carried out, maps (usually A0 size) of the area are required, viz.
a general Site Location map of the area (usually O.S. Map 1:2500 scale) on which the channels/watercourses on
which works are proposed, together with the area to benefit under the scheme are marked; chainage distances
along watercourses are marked for reference;
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more detailed map(s) of the area on which the channels/watercourse on which works are proposed, together with
the area to benefit under the scheme are marked. In addition, such map(s) are also endorsed with letters/numbers,
which are cross referenced with corresponding letters/numbers in Schedule B (mentioned earlier) to enable
property owners and general public to identify the areas on which specific elements of work are proposed.
DRAWINGS/PLANS/SECTIONS:
These comprise of drawings of existing cross and longitudinal sections of the channel / watercourses on which works
are proposed together with the corresponding design sections. They also include drawings/plans of structures, etc.
proposed to be constructed under the scheme. (Usually A1 size)
ENVIRONMENTAL IMPACT ASSESSMENT REPORT (EIAR):
The environmental impacts of the scheme proposals are assessed by separate specialist consultants as the design is
progressed and on completion, when mitigating measures may be incorporated into the design or mentioned for
consideration in the EIAR. The EIAR document forms part of the statutory exhibition documentation and copies are
made available for sale to the public via the Scheme website or in CD/DVD format from Galway County Council, as are
Non-Technical Summaries of the EIAR.
INTERFERENCE NOTICES:
Each reputed proprietor, owner and rated, other occupier, Utility companies, and/or the beneficiaries of a right of way,
fishing right or other similar right of lands/property proposed to be interfered with under the scheme is entitled to
receive a Notice detailing the type and extent of the works proposed to be carried out on their respective
lands/property, access routes, along with any interference with rights associated with the property as a result of the
scheme works on the particular property and any future restrictions. This Interference Notice advises the individual
mentioned therein not only of the availability for public inspection of scheme documents at certain specified locations
and times in the affected area but also details the specific works to be carried out on their lands/property. The latter
information for this Notice is obtained from Schedule B of the Schedules (mentioned earlier). The Notice (usually A4
portrait) also advises them of their entitlement to submit such observations, if any, they may wish to make concerning
the scheme within one month of receipt of the Notice. The Consultant will prepare these notices and they will then be
sent to the reputed proprietor, owner, and rated or other occupier at least one week before the scheme is exhibited.
Interference Notices should include copies of relevant drawings, including plan layouts, benefit areas, possible access
routes, works areas and property location drawings with works superimposed. Access for future work on channels
should be referenced in the Interference Notices.
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APPENDIX I
CONFIRMATION DOCUMENTS
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Confirmation documents comprise of updated versions of Exhibition documents:
(a) Schedules outlining in detail the drainage and other works proposed to be carried out under the scheme; the
names of the reputed proprietors, owners and rated or other occupiers of the lands proposed to be interfered
with under the scheme.
(b) Maps outlining the waters and watercourses to be dealt with; the lands to be drained or otherwise improved
by the scheme; lands proposed to be compulsorily acquired or substantially interfered with under the scheme.
(c) Drawings / Plans / Sections outlining details of the designed works proposed to be carried out under the
scheme.
(d) Environmental Impact Assessment Report An Environmental Impact Assessment Report, including a Non-
Technical Summary is required for the preferred scheme option. The EIAR shall be prepared to meet the
requirements of the EIA Directive 2014/52/EU and the Arterial Drainage Acts 1945 and 1995 as amended (The
EIAR to be supplied by the Environmental Consultants).
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APPENDIX J
PROJECT MANAGEMENT SERVICES
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PROJECT MANAGEMENT SERVICES
The Consultant’s Representative shall act as Project Manager for the duration of the Contract.
The Project Manager will be responsible for the preparation of an overall schedule of the tasks to be carried out by
the various members of the Consultant’s team and the organisation of their delivery on time and to a satisfactory
quality standard.
The Project Manager will attend each month at meetings of the Steering Committee to report on progress and to
ensure that any queries that the Steering Committee have will be answered promptly by the relevant team
member. This report on progress will be in writing and will be of a form which clearly shows the performance of
the project and describe the work undertaken during the previous period since the previous Progress Report was
submitted, and shall clearly and fully detail technical findings, proposals and any problems encountered or
foreseen, with associated proposed solutions, and (if necessary) provide and updated work programme for the
remainder of the project for the approval of Galway County Council, including critical dates for delivery of
information, decisions or other inputs from Galway County Council, other members of the Steering Group or other
parties.
The Project Manager will arrange for the taking of minutes at meetings of The Steering Committee. These minutes
shall include a summary of actions arising with associated responsibilities and deadlines and submit the minutes to
all Steering Group Members for review no later than three working days after the date of the meeting. The first
Steering Group meeting shall be held within two weeks of appointment of the Consultants at which the Consultant
shall provide a full and detailed project programme for Stage I of the Project for discussion with, and approval of
the Steering Group.
The Project Manager will put in place a filing system to manage all documentation generated by the Project. The
Project Manager will agree on a filing system with The Project Coordinator. The Project Manager will maintain a
daily record of the Works. The Project Coordinator will at all times have access to said files and documentation. On
completion of the Works all of the files will be handed over to The Project Coordinator.
The Project Manager will be responsible for coordinating the interaction between the Consultant’s team and Trinity
College Dublin, with regards to the modelling of the Kinvarra West lowlands and the acquisition of model outputs
from the TCD project.
The Project Manager will have recorded the details of interference to each affected property owner. A separate
set of details will be prepared for each affected property owner. These details will be available on request to The
Project Coordinator. These details will include dates / duration of interference, description of pre-works situation,
description of interference, information on how the works might have impacted on future development of
property, initial assessment of loss of income due to works both during and after works, area of land loss, and
measured details of other property disturbance. Information should also be provided on the benefits of the
interference or the scheme, including any mitigation or improvements carried out as part of the works and any pre-
scheme information supporting evidence of previous flooding. These interference details are most important as
they form the basis for the assessment of compensation to the affected landowners and in the event of a dispute
on the level of said compensation will be scrutinised at arbitration.
The Project Manager will be required to make available relevant team members to meet and liaise with persons or
groups affected either directly or indirectly by the scheme. These meetings could take place outside of normal
working hours and might be with affected property owners and occupiers, business interests, sporting bodies and
elected members of relevant local authorities.
The Project Manager will notify the Project Coordinator as soon as he becomes aware of likely:
Circumstances likely to require change in agreed scope of works
Construction variation required beyond the Consultants authority
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Insurance default
Information, access or assistance urgently needed
The Project Manager will notify The Project Coordinator on any changes to any members of the team, and furnish
him/her with CVs of suggested replacement members for approval by The Client which approval or otherwise will
be communicated to The Project Manager within five working days. The Client may decide at their discretion to
have the suggested replacement attend at an interview.
The Project Manager will deal with all queries on the Project by members of the public and will where relevant
provide information to The Client to enable replies to be made. When queries are received from the media or
politicians, the Project Manager shall prepare an appropriate draft response and forward same to Galway County
Council for review and issue.
The Project Manager will have the responsibility for ensuring the Project Website is developed and maintained to
the Clients satisfaction.
The Project Manager will be responsible for ensuring, in so far as is reasonable, the timely delivery of specialist
services by members outside the Consultant’s team. These would include Topographical Surveys, Geotechnical
Surveys, Archaeological Services and Environmental Monitoring. The Project Manager’s role with regards to
external service providers will also include but will not be limited to: liaising, quality checking, payment approval,
H&S compliance checking and progress reporting.
The Project Manager will have the responsibility for making any presentations on the project to stakeholder groups
including Elected Councillors and Traffic Management Committees.
The Project Manager will be responsible for the provision of monthly reports on works status and expenditure
status and contract variation status.
The Project Manager will have among his qualifications that of Chartered Engineer.
The Project Manager may carry out another role in the Project Team.
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APPENDIX K
GUIDE TO PROCEDURES AND OFFICES FOR TITLE RESEARCH
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LAND REGISTRY
Ability to abstract relevant information from maps and folios, and in particular, from the primary folios. Maps on 6” are
to be regarded as Primary maps since they were registered from the Estate Map. On-line maps are helpful but
boundaries are not available for all counties yet, and on-line folios do not provide the history of the property. At public
counter only.
VALUATION OFFICE
Invaluable for research into unregistered lands. Research back to Griffith’s Valuation should be completed for all lands,
registered or unregistered. Maps and last occupier/ratepayer are on-line, but only commercial property gives more
recent occupiers since rates are no longer paid by the general public so research should then take place in the Registry
of Deeds for sales. At public counter and self-search in Archive room.
LAND COMMISSION
Contains original Estate Papers with maps, vesting orders, agreements, schedules of area and original title documents
with history of estate. Information on turbary rights at the public counter usually.
REGISTRY OF DEEDS
Registers deeds by two methods. By Baronies and Townlands in Location Books from 1708 to 1949 and by Grantors
Surname from 1708 to 1960 in Grantor’s Books. From the 1960’s the information is available on-line with the exception
of a couple of years in the early 1970’s. Grantors names can usually be got from the Valuation Office archives. Titled
grantors must also be checked under Family name, i.e.: Earl of Portarlington/Dawson. Transfers and Sales of property
may be registered here but no maps are available. Public counter and self-search.
NATIONAL ARCHIVES
Contains information on Crown Grants, Lodge’s Record of the Rolls, Books of Survey and Distribution, Quit Rents, Lec.
Conveyances, Calendar of Wills and Testamentary Indices. Many of these are available on Micro-Fiche. Registration of
Wills is available in book form up to 1983 in Archives. Those that did not survive the 1922 fire are indexed by name.
Self-search usually but help is available from staff.
PROBATE OFFICE
Registers Wills from 1983 onwards on-line. Approximate date of death and address is needed. Public Counter.
COMPANIES OFFICE
Gives names of Directors, company Secretaries and Articles of Association. Files available but most information are now
on-line. Public counter.
NATIONAL LIBRARY
Useful for Death notices of Family Histories in newspapers. Thom’s Directory and Burke’s Peerage and Burke’s Irish
Landed Gentry are also available here. Micro-fiche and self-search.
Copies of most of the above research can be ordered from the relevant office.
SITE VISITS
Site Visits will be carried out to:
(i) Confirm that the boundaries as shown on the drawings correspond with that on the ground. This will consist of
a visual survey only – no instruments will be used. Photographs will be taken where deemed necessary.
(ii) Confirm that ownership / occupancy details sourced through searched are correct and up to date or
where searches did not yield any result to seek assistance in tracing title to the property.
(iii) Agree a suitable address for service of Statutory Notices.
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Advance notification of site visits should be issued by letter where possible to do so. A record of all site visits should
be kept on file.
Note: The number of site visits should be kept to a minimum. Phone calls and correspondence should be used where
possible.
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APPENDIX L
TRINITY COLLEGE DUBLIN RESEARCH AND MODELLING
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Trinity College Dublin Research and Modelling Research into the intermittent groundwater (and/or pluvial) flooding of turloughs in the lowland karst area of south Galway has been undertaken at the Department of Civil, Structural and Environmental Engineering in Trinity College Dublin (TCD) since 2003 and is on-going.
Background: The karst of the south Galway lowlands is underlain by highly permeable epikarst with a well-developed conduit and
cave system dispersed throughout the catchment. The area is also known to be underlain by more ancient paleo-karst
which may also interact with the shallow epikarst and conduit systems providing alternative discharge methods.
The outlet for the catchment is through a submarine groundwater discharge (a series of springs located at the intertidal
zone of the bay) at Kinvarra Bay predominantly occurring via two springs, Kinvarra West and Kinvarra East. Kinvarra
West serves as the outlet of a major, primarily allogenically fed, karst conduit network, while Kinvarra East discharges
water from more diffuse/autogenic sources. Discharge from these springs occurs intertidally and as such, their flow
rates cannot be measured using traditional methods.
The flooding which occurs annually in the majority of the turlough basins across the catchment is mainly due to
insufficient capacity of the underground karst system to take increased flows following excessive precipitation events,
causing the conduit-type network to surcharge. Continuous water level measurements have been taken in five linked
turloughs, see Appendix L(4), in the lowland karst area of south Galway over an extended period spread over various
research projects at TCD mainly under the supervision of Dr Laurence Gill and Mr Paul Johnston. These water level
fluctuations, in conjunction with river inputs and precipitation, have been used to simulate the hydrogeological controls
forming the main hydraulic system beneath the ground.
A model of the karst network has been developed using a pipe network model with the turloughs represented as ponds.
The contribution to the karst network from diffuse flow through the epikarst via the matrix and fracture flow has also
been modelled using a combination of an infiltration module and network of permeable pipes. The model has been
used to predict the groundwater discharge to the coast at Kinvarra via the main Kinvarra West spring. This model is
currently been extended to include other turloughs which link to the main conduit system to the south of the catchment
and is being developed to include 2D terrain mapping of the catchment allowing overland flood routing to be modelled.
A number of research publications (Gill et al., 2013; McCormack et al., 2014; Naughton, 2011; Naughton et al., 2012)
summarise the main of areas research undertaken to date.
Current Modelling: The latest aspect of the TCD research involves utilising LiDAR data for the catchment in combination with the existing
pipe network model to produce 2D models of the catchment. This will enable flood estimation to take place beyond the
time period for which calibration data are available. Overland flood routing is being matched to the mapped flood
extents of recent extreme flood events (2009 & 2015). The flood modelling will also investigate the effects of carrying
out various flood alleviation measures across the catchment. A working model is scheduled to be in place towards the
latter end of 2017.
A range of flood alleviation scenarios will be modelled ranging in scale from small local works to large catchment-based
schemes such as the construction of flood alleviation channels. This research is on-going and the net effects of climate
change across the catchment and the impacts on potential flood alleviation works will also be investigated.
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Available Outputs: The output from the TCD research project will be made available to the Consultant which will include flood maps, flood levels and hydrographs and the modelled impacts of various flood alleviation measures which have been modelled. The pipe network model will remain the intellectual property of TCD and will not be provided to the Consultant. The consultant will be required to liaise with TCD and to inform themselves of the limitations of the flood modelling and the assumptions which have been made during the research project. The Consultant shall locate, copy (if necessary), review, quality control, format (if necessary), interpret and make use of (as relevant) all potentially relevant information on the research which has been carried out at TCD to date, including, but not necessarily limited to, those referred to below:
Gill L.W., 2010. Modelling a network of turloughs, PhD Thesis, University of Dublin, Trinity College, Ireland.
Naughton, O., 2011. The Hydrology and Hydroecology of Turloughs. PhD Thesis, University of Dublin, Trinity College, Ireland.
Naughton, O., Johnston, P.M., Gill, L.W., 2012. Groundwater flooding in Irish karst: The hydrological characterisation of ephemeral lakes (turloughs). Journal of Hydrology, 470– 471(0)
Gill, L.W., Naughton, O., Johnston, P.M., 2013. Modelling a network of turloughs in lowland karst. Water Resources Research, 49(6): 3487-3503.
Gill L.W., Naughton O., Johnston P.M. (2013). Characterisation of hydrogeological connections in a lowland karst network using time series analysis of water levels in ephemeral groundwater-fed lakes (turloughs). Journal of Hydrology 499, 289-302.
McCormack, T., 2014. Quantifying Nutrient Dynamics Through a Lowland Karst Network. PhD Thesis, University of Dublin, Trinity College, Ireland.
McCormack, T., Gill, L.W., Naughton, O., Johnston, P.M., 2014. Quantification of submarine/intertidal groundwater discharge and nutrient loading from a lowland karst catchment. Journal of Hydrology, 519, Part B: 2318-2330.
Naughton, O., Johnston, P.M., McCormack, T., Gill, L.W., 2017. Groundwater flood risk mapping and management: examples from a lowland karst catchment in Ireland. Journal of Flood Risk Management 10: 53–64. doi:10.1111/jfr3.12145
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APPENDIX M
MAPPED DETAILS FOR SCHEME
M(1) – PRINCIPLE STUDY AREA
M(2) – DESIGNATIONS
M(3) – EXTENT OF FLOOD EVENTS
M(4) – LOGGERS AND GAUGES
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APPENDIX N
Flood Defence Asset Survey Requirements
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N1. INTRODUCTION
N1.1 Definition of Flood Defences
Flood Defence Assets (or ‘flood defences’) are defined as structures or features that were constructed to provide a
formal flood defence function (‘formal flood defences’), including those that may be in poor condition, and also those
that may have been built for other purposes but that, in the opinion of the Consultant, would provide a flood defence
function (‘informal effective flood defences’). They do NOT include structures that were not constructed to provide a
formal flood defence function and that, in the opinion of the Consultant, would fail to provide a flood defence function
due to structural weakness, porosity or other such reasons (‘informal ineffective flood defences’), such as garden walls
or embankments perforated by uncontrolled culverts.
N1.2 Scope of Survey
The flood defences for which the Consultant shall perform the duties set out herein are limited to those that are within
the Study Area as shown in Figure M(1) and that are either
within an APSR, or,
alongside, in or over a relevant watercourse The flood defences include all assets installed as part of the scheme and pre-existing channels, bridges, culverts, sluices, embankments that provide a flood defence function. The Consultant shall prepare, and agree with the Steering Group in advance of commencing the flood defence asset
survey, a list and location of the flood defence assets that shall be included within the flood defence asset survey.
N1.3 Consultants Duties
The services and duties of the Consultant under the Flood Defence Asset Survey shall include:
A geometric survey of the flood defences
A visual condition survey (measure of risk of failure, residual life and maintenance / replacement requirements) of the flood defences
Entry of all geometric and visual condition survey data and other related data into a report that will allow for a comprehensive maintenance plan to be readily developed for the scheme. This data shall include:
o Geometric data from the geometric survey of the flood defences
o Geometric data supplied from geometric survey of flood defences undertaken under other contracts
o Entry of all the visual condition survey data
o Entry of photograph/s for each flood defence
o Entry of the flood defence asset geographic location into GIS map application
A detailed description of the services and duties the Consultant shall deliver under the flood defence asset survey are
set out below.
N1.4 Progress Reporting
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During the survey the Consultant shall be required to submit regular reports on the progress of the survey. The format
of these reports shall be agreed at a start-up meeting.
On completion of the first progress report (or sooner if agreed), the Consultant shall submit to GCC a sample of the
survey data obtained. The survey team shall then attend a meeting with GCC to discuss the data submitted. Details of
this initial review meeting can be decided at the start-up meeting.
The Consultant shall alert GCC of any additional flood defence assets observed during the survey that he/she feels
should be included in the survey. The Consultant shall record all bridges along the watercourses as detailed below and
report on the conditions of those bridges.
N2. HEALTH AND SAFETY
N2.1 Health and Safety Requirements
The Flood Defence Asset Survey shall be undertaken in full accordance with the Health and Safety requirements as set
out in Section 2.5.
N2.2 Hazard and Risk Assessment
A Hazard and Risk Assessment must be undertaken for the Flood Defence Asset Survey. Prior to commencing any survey
work on site the Consultant shall meet with GCC to discuss the Hazard and Risk Assessment. The Consultant shall circulate a
copy of the Hazard and Assessment to along with any updates to all members of the Steering Group and survey team. The
site specific Hazard and Risk Assessments should be submitted to GCC prior to any site work beginning.
N2.3 Confined Spaces
Culverts and other flood defence assets that form a confined space shall be inspected as far as is possible from both the upstream and downstream extent but will not at any time be entered under this commission. If it is not possible to make an accurate assessment of the condition and construction from either the upstream or downstream extent, or if one or both of these is not accessible, a recommendation will be made for that asset to be inspected by a competent confined space specialist or CCTV.
N3. FLOOD DEFENCE ASSET GEOMETRIC SURVEY
N3.1 Consultants Duties
The Consultant shall undertake the Flood Defence Asset Geometric Survey as part of the Channel and Structure Survey,
as set out in Section 4.3 and Appendix N, and shall include this data in the Flood Defence Asset Report.
N4. VISUAL CONDITION SURVEY
N4.1 Consultants Duties
The Consultant shall be required to undertake a visual inspection and condition survey of the flood defences, and their
component assets, structures and elements, to assess the physical condition of the defence that may be used as a basis
to determine its likelihood of failure and need for maintenance, renewal or replacement.
The Consultant shall record specific data as part of the visual condition survey as necessary to provide a comprehensive
report on the asset.
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Geotechnical analysis or other such sampling will not be required as part of the condition assessment under this Project.
The Consultant shall photograph each structure that forms part of all surveyed assets. Each photograph shall be saved
into a digital common picture format (e.g., jpg, tiff, bmp) not exceeding 100kb and shall be saved, with a filename in a
manner that will permit easy identification.
The Consultant shall carry out an overall condition assessment of all bridges in APSRs and relevant watercourses in the
study area and include the bridge assessment in the Flood Defence Asset Report. The report is to include details of the
bridge such as name, location, watercourse, bridge type, condition assessment, comments etc.
N5. ACCESS TO LANDS
N5.1 Letter of Introduction
GCC will provide the Consultant with a letter of introduction for landowners; which will introduce the Consultant,
describe the purpose of the survey and request landowners to make access available to the Consultant.
N6. DELIVERABLES
N6.1 Hardcopy & Digital Plans
The Consultant shall deliver 3 sets of A3 drawings detailing the location and extents of the Flood Defence Assets that
have been surveyed, overlaid on the highest scale of available OSi mapping. These shall form part of the handover report
detailed below.
The Consultant shall also supply the above dataset in digital format compatible with GIS and CAD software. All digital
data shall be supplied on either CD or DVD.
N6.2 Digital Metadata
Metadata, including the date and time of the survey, shall be provided for all survey information. The details of the
required metadata formats shall be agreed at the Start-up meeting.
N6.3 Digital Photographs (one set on CD or DVD)
The Consultant shall provide digital photographs of every Flood Defence Asset surveyed. The photographs shall cover
the full structure list for each asset and provide multiple viewpoints of the defence.
N6.4 Handover Report
The Consultant shall prepare the Flood Defence Asset Report upon completion of the defence asset work. The report
shall include an overview of the processes used during the survey and data entry phases.
The report shall be a record of assets surveyed and the report shall also contain the bridge condition information as
specified earlier.
N6.5 Format of Deliverables
The exact format of all deliverables will be decided at the Start-up meeting.
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APPENDIX O
Assessment of Degrees of Confidence
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APPENDIX O –ASSESSMENT OF DEGREES OF CONFIDENCE
The Consultant shall assess the uncertainty in the estimated flood flows and levels, as set out in Section 6.4.3. Based on
the uncertainty in flood levels, the Consultant shall estimate the degree of confidence in the flood extent (referred to
as ‘shoreline uncertainty’), using the method set out below7.
G1. Method for Determining Degrees of Confidence in Flood Extents
The shoreline location uncertainty is a function of water level uncertainty and floodplain topography in the region of
the shoreline. Information is required on the level uncertainty and sensitivity of the shoreline to changes in water level.
Flood hazard mapping studies will generally produce flood maps at a number of return periods, and these can be used
to estimate shoreline uncertainty as shown in Figure G1, using the 100 and 1000 year shorelines as an example. The
shoreline uncertainty is given by:
1001000
1001000
h
hxx
yUncertaint
yUncertaint [1]
Where:
yUncertaintx is the flood outline location uncertainty,
1001000x is the distance between the 1000 and 100 year flood outlines,
yUncertainth is the uncertainty in model predicted water levels (e.g. derived from the scoring method), and,
1001000h is the difference in water levels between the 1000 and 100 year model predictions.
Figure G1: Distance to nearest 1000 year shoreline point may not be representative of true distance
between shorelines (left). Distance to the nearest 100 year shoreline point from the 1000 year shoreline is
more representative (right).
7 Uncertainty Mapping Report, Halcrow (on behalf of OPW), 2008
100 yr
1000 yr
100 yr
1000 yr
Nearest point
Nearest point Take maximum of
these distances
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The shoreline uncertainty is therefore linearly interpolated or extrapolated from the difference between the 100 and
1000 year shorelines. ∆h1000-100 can be found for each shoreline point (i.e. each vertex of the polyline defining the
shoreline) from raster data of predicted water levels, and if these data are unavailable (it is often only a by-product of
the flood mapping process, and therefore may not be kept from previous studies), ∆h1000-100 can be calculated from the
flood extent and a Digital Terrain Model.
Δx1000-100 is defined by measuring the difference between each 100 year shoreline point and its nearest 1000 year
counterpart. This may give an unrepresentative value for the distance, for example where the distances between the
shorelines vary significantly (G1). An alternative measure is therefore also defined by measuring the minimum distance
between each 1000 year shoreline point and the 100 year shoreline. The maximum of these values is taken as the
distance between the shorelines, and this measure has been found to represent well the sensitivity in shoreline
locations.
By using this method, the uncertainty in flood outline location can be estimated based not only on water level
uncertainties, but on the sensitivity of flood outlines to these water levels. Thus sensitive areas (i.e. of low lateral
floodplain slope) will be assigned a higher uncertainty, and areas where the flood outline is well constrained by steep
bounding slopes will be assigned a lower sensitivity, even if these two areas have the same uncertainty in water levels.
The two main sources of uncertainty in flood outline location, water level uncertainty and the sensitivity of the shoreline
location to changes in water level, are thus represented in this simple model.
This method has been implemented in a simple command-line driven tool (UMap) operating with ASCII raster grids and
ESRI shapefiles. The shoreline location uncertainty results are smoothed and then discretised into three classes, to allow
them to be displayed clearly in GIS software. A number of polylines are output in a single shapefile, each representing
a length of shoreline of the same uncertainty class, with the uncertainty given in the attribute table.
Figure G2: Shoreline uncertainty derived from 100 year and 1000 year flood outlines
The method is also applicable to shoreline mapping derived from sources other than 1D models (such as 2D models,
tidal flood extents created by GIS etc.)
1000 year level
100 year level
Shoreline shows little
sensitivity to water level
Δx1000-100
Shoreline is
highly sensitive to
water level
100 year level+Uncertainty
ΔxUncertainty Δh1000-100 ΔhUncertainty