URBAN STREAM REHABILITATION. CASE STUDIES Contents: 1Approach 2Case studies 3Impacts of urban river...

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URBAN STREAM URBAN STREAM REHABILITATIONREHABILITATION

CASE STUDIESCASE STUDIES

Contents:Contents:11 Approach Approach

22 Case studiesCase studies

33 Impacts of urban river rehabilitationsImpacts of urban river rehabilitations

44 Planning and implementation process Planning and implementation process

55 Aesthetic evaluation methods Aesthetic evaluation methods

66 Social appraisal and participationSocial appraisal and participation

77 Rehabilitation techniquesRehabilitation techniques

88 Summary and conclusionsSummary and conclusions

1 ApproachApproach

• Survey on urban rehabilitation schemes (Europe, others)Survey on urban rehabilitation schemes (Europe, others)

• Case study approachCase study approach

- urban setting- urban setting

- rehabilitation (ecological improvement) - rehabilitation (ecological improvement)

- scheme completed - scheme completed

• Standardised enquiry formStandardised enquiry form

• Quantitative and qualitative analysis of each Quantitative and qualitative analysis of each casecase

• Comparison of tools, techniques, procedures Comparison of tools, techniques, procedures and impactsand impacts

high good mod. poor bad high good mod. poor bad

I Ecological State1 Biological State

a) phytoplankton b) macrophytes and phytobenthosc) benthic invertebrate faunad) fish fauna

2 Hydro-morphologya) hydrological regimeb) river continuityc) morphological conditions

Ecological and Chemical State

State of water body (according Water Framework Directive ) before and after implementation

evaluation scaleparameter

state of water body before revitalization (reference date: ………...)

state of water body after revitalization (reference date: ………...)

Urban River Basin Enhancement Methods (URBEM) Case Studies of Existing Successful River Enhancement Projects(A) Ecological and Chemical State

1. Approach

1 Selected case studies

2 Comparison of General Characteristics

2. Case studies -Brief description

Austria:

Vienna - Wienfluss

Germany:

Munich – Isar

Italy:

Florence – Mugnone Brook

Switzerland:

Zurich – Brook Concept

Albisrieder Dorfbach2. Case studies -Brief description

Czech Republic:

Chrudim – Náhon

Cananda:

Toronto – Mud Creek

United States:

Wilmington – Christina River

1 Objectives of urban river 1 Objectives of urban river rehabilitationrehabilitation

2 Objectives of ecological 2 Objectives of ecological improvementimprovement

3 Length of urban river rehabilitation 3 Length of urban river rehabilitation schemesschemes

4 Total costs of urban river rehabilitation 4 Total costs of urban river rehabilitation schemesschemes

2 Case studies -Case studies - CharacterisationCharacterisation

2. Case studies -Characterisation

Objectives of ecological improvementin urban rehabilitation projects

8 (36%)

7 (32%)

11 (50%)

5 (23%)

6 (27%)

2 (9%)

3 (14%)

0 2 4 6 8 10 12 14

other parameters

vegetation

target species

lateral connectivity

continuum

stream morphology

hydrlology / hydaulics

w ater quality

number of namings (n=22)

Objectives of urban river rehabilitation projects

9 (39%)

22 (96%)

6 (26%)

10 (43%)

8 (35%)

5 (22%)

8 (35%)

0 5 10 15 20

others

education

Public involvement

urban upgrading

amenity/recreation

visual improvement

ecological improvement

f lood control

number of namings (n=23)

Total costs of rehabilitation projects and costs per meter

12,040

1,5150,500 0,576 0,007 0,310 0,005

0,190 0,135 0,027

18,100

0,6041,275

12,000

27,00026,0002.907

333230 245

2.9573.385

2.1032.014

case studiy

io €

10.000

er (€

total costs

costs per meter

land purchase costs

12.06715.000

1.000 TEU 1.000 TEU

500 TEU

5.600 TEU

Length of rehabilitated river sections and size of area

30 100

113024866

40 80,02

100 136

case study

length of section

size of rehabilitated area

9,5 km 8,0 km550

area size: if not mentioned = no data

3. Impacts of river rehabilitation 3. Impacts of river rehabilitation schemes schemes

• Ecological impactsEcological impacts

• Social impactsSocial impacts

• Economic impactsEconomic impacts

• Impacts on public health and safetyImpacts on public health and safety

3. Impacts of river rehabilitation schemes

Hydro-morphologic conditions of urban waters before and after rehabilitation

case study

hydrological regime

river continuity

morphological conditions

very good

moderate

Biological conditions of urban waters before and after rehabilitation

case study

macrophytes and phytobenthos

benthic invertebrate fauna

fish fauna

very good

moderate

Overall acceptance of urban river rehabilitation sites before and after rehablitation

case study

Frequency by local population

Frequency by tourists

Frequency by school classes

above average

average

below average

Impact of urban river rehabilitation schemeson fish fauna

1 (6%)

5 (31%)

10 (63%)

8 (50%)

2 (13%)

1 (6%)

5 (31%)

0 2 4 6 8 10 12

moderate

very good

number of case studies

after rehabilitation (n=16)

before rehabilitation (n=16)

Visual and spatial experience along urban river rehabilitationsections before and after rehabilitation

case study

presence of focal pointspresence of view ing pointsdistinctive open spacesvisual aversion experiences

above average

average

below average

Morphological conditions and biological indicators of urban waters before and ofter rehabilitation

case study

morphological conditionsbenthic invertebrate faunafish fauna

very good

moderate

• Initiation of urban river rehabilitation projectsInitiation of urban river rehabilitation projects

• Site selectionSite selection

• Project managementProject management

4. Planning and 4. Planning and implementation processimplementation process

• Almost 90 % public administration initiationsAlmost 90 % public administration initiations

• primary initiative usually from citizen groupsprimary initiative usually from citizen groups

• 20 % responding to legal demands20 % responding to legal demands

• Most aim at rehabilitation of certain river sectionMost aim at rehabilitation of certain river section

• Selection methods on basin or city scale, determination of Selection methods on basin or city scale, determination of potential for rehabilitationpotential for rehabilitation

• 21% used some kind of site selection method 21% used some kind of site selection method

4. Planning and implementation 4. Planning and implementation processprocess

19751980198519901995200020052010

case study

initiation idea funding process planning process

implementation post-implementation appraisal

Initiators of urban river rehabilitation projects

1 (4%)

6 (26%)

9 (39%)

20 (87%)

0 4 8 12 16 20

Other initiatives

Interest group initiative

Civic initiative

Public administration initiative

number of namings(% of case studies, n=23)

5. 5. Aesthetic EvaluationAesthetic Evaluation

Aspects of Aesthetic Perception and Aspects of Aesthetic Perception and Recreational UsabilityRecreational Usability

• extracted from Part B and Part C of the extracted from Part B and Part C of the enquiry, state conditions and enquiry, state conditions and implemented measuresimplemented measures

• quite diverse understanding of what quite diverse understanding of what aesthetics for urban rivers isaesthetics for urban rivers is

5. 5. Aesthetic Aesthetic Evaluation Evaluation

74.00%

35.00%

30.00%

78.00%

70.00%

35.00%

13.00%

22.00%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Visual and Spatial Aspects

Aspects of Smell and Sound

Remedy of Aversion Experience

Aspects of Accessibility

Aspects of Social and Cultural Infrastructure

Aspects of Accident Prevention

Aspects of Public Health

Aesthetical Evaluation methods

Aspects of Aesthetic Perception Aspects of Aesthetic Perception and Recreational Experienceand Recreational Experience

Aesthetic Evaluation MethodsAesthetic Evaluation Methods• expert assessmentsexpert assessments• surveyssurveys

5. 5. Aesthetic EvaluationAesthetic Evaluation

74.00%

35.00%

30.00%

78.00%

70.00%

35.00%

13.00%

22.00%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Visual and Spatial Aspects

Aspects of Smell and Sound

Remedy of Aversion Experience

Aspects of Accessibility

Aspects of Social and Cultural Infrastructure

Aspects of Accident Prevention

Aspects of Public Health

Aesthetical Evaluation methods

6.Social appraisal and 6.Social appraisal and Public Public

Involvement Involvement • Legal requirements for public Legal requirements for public

participationparticipation

• Stakeholders and Identification of Stakeholders and Identification of StakeholdersStakeholders

• Informing stakeholders Informing stakeholders

• Involving Stakeholders Involving Stakeholders

• Stewardshop and AdvocacyStewardshop and Advocacy

6.Social appraisal and Public 6.Social appraisal and Public Involvement Involvement

• legal requirements for public information legal requirements for public information and involvement have been mentioned for and involvement have been mentioned for almost half of the projecsalmost half of the projecs

• how did project responsibles deal with this how did project responsibles deal with this legislation?legislation?

• involvement from public information to involvement from public information to comprehensive participation of diverse comprehensive participation of diverse stakeholder groupsstakeholder groups

48.00%

61.00%

87.00%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Legal Requirements for Public Participation Legal Requirements for Public Participation

ExceededProjects w ith any Kind of Public Participation

• citzen: residents, property ownerscitzen: residents, property owners

• NGOs on national, regional and local NGOs on national, regional and local levellevel

• commercial assosiations (Anacostia commercial assosiations (Anacostia River Business Coalition)River Business Coalition)

• Politicians (Isar)Politicians (Isar)• Identification of stakeholders Identification of stakeholders (Kaitzbach(Kaitzbach, , SkerneSkerne))

6.Social appraisal and Public Involvement - 6.Social appraisal and Public Involvement - Stakeholders Stakeholders

87. 00%

17. 00%

65. 00%

26. 00%

43. 00%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Citizen

Political Groups

NGO's (Non-Government Organisations)

Commercial Associations or Single Businesses

other Social Groups

6.Social appraisal and Public Involvement - 6.Social appraisal and Public Involvement - Stakeholders Stakeholders

• increase of social awareness and increase of social awareness and appraisalappraisal

• first step to public participationfirst step to public participation• Guided toursGuided tours• Information boards onsite Information boards onsite • Exhibitions Exhibitions • InstallationsInstallations

6.Social appraisal and Public Involvement – Informing 6.Social appraisal and Public Involvement – Informing Stakeholders Stakeholders

96. 00%

57. 00%

43. 00%

52. 00%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Paper Related (Brochures, Billboards,New spaper/Journals)

World Wide Web

Local TV-Station/Radio

Presentations, Lectures etc.

6.Social appraisal and Public Involvement – Informing 6.Social appraisal and Public Involvement – Informing Stakeholders Stakeholders

• Collection of ideas and site selection Collection of ideas and site selection

• competitionscompetitions• surveys surveys • workshops workshops • public discussion meetingspublic discussion meetings

• on site involvement (Wandse, Toronto)on site involvement (Wandse, Toronto)

6.Social appraisal and Public Involvement – Involving 6.Social appraisal and Public Involvement – Involving Stakeholders Stakeholders

57. 00%

65. 00%

35. 00%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

In Course of Different Project Phases

Collection of Ideas

Site Selection

Voluntary Clean-up Events

6.Social appraisal and Public Involvement – Involving 6.Social appraisal and Public Involvement – Involving Stakeholders Stakeholders

• active support for river enhancement active support for river enhancement through stakeholdersthrough stakeholders

• Partnerships: brook sponsorships, Partnerships: brook sponsorships, NGOs, coalitionsNGOs, coalitions

• continuous activities: newsletter, continuous activities: newsletter, guided tours, school days, monitoringguided tours, school days, monitoring

• single events: inauguration of single events: inauguration of schemes, river related festivals schemes, river related festivals

• information for rivers non-project information for rivers non-project relatedrelated

6.Social appraisal and Public Involvement 6.Social appraisal and Public Involvement Stewardship and Stewardship and advocacyadvocacy

30. 00%

52. 00%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Partnerships and Coalitions for River Stew ardship

River Advocacy through Continuous Activities

River Advocacy through Single Events

6.Social appraisal and Public Involvement 6.Social appraisal and Public Involvement Stewardship and Stewardship and advocacyadvocacy

7. 7. Rehabilitation techniquesRehabilitation techniques

• Improving Water QualityImproving Water Quality

• Improving Hydrology and Improving Hydrology and HydrodynamicsHydrodynamics

• Improving Stream ConnectivityImproving Stream Connectivity

• Restoration Techniques for Aquatic Restoration Techniques for Aquatic and Riverine Ecosystemsand Riverine Ecosystems

• Techniques Incorporating Features to Techniques Incorporating Features to Improve Public Health and SafetyImprove Public Health and Safety

• Measures Practiced Basin WideMeasures Practiced Basin Wide

7. 7. Rehabilitation techniquesRehabilitation techniques

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Measures to Reduce Point Sources of Pollution

Measures to Reduce Non-Point Sources of Pollution

Ameliorationg Stream Hydrology

Measures to Control the Sediment Balance

Channel Reconstruction by Improving LongitudinalConnectivity

Channel Stabilisation and Enhancing LateralConnectivity

Re-establishing Vertical Connectivity

Restoration of Aquatic Vegetation

Restoration of Riparian Vegetation

Restoration of Aquatic Populations and Fisheries

Groups of individual measures can be found aiming at the Groups of individual measures can be found aiming at the same rehabilitation target same rehabilitation target

7. 7. Rehabilitation techniques – measure Rehabilitation techniques – measure groupsgroups

Measures: Measures:

wet ponds with extended detentionwet ponds with extended detentiongrassy filter strips grassy filter strips constructed wetlandsconstructed wetlands bioretentionbioretention structural enhancement structural enhancement silt trapping devicessilt trapping devices

7. 7. Rehabilitation techniques – water Rehabilitation techniques – water qualityquality

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Construction of biological treatment plants

Stormw ater storage and treatment

Sew er separation

Sediment control (erosion prevention)

Control of chemical pollutants

7. 7. Rehabilitation techniques – water Rehabilitation techniques – water qualityquality

• one fourth of case studies used one fourth of case studies used stormwater infiltration for detaining stormwater infiltration for detaining peak flowpeak flow

• measures ‘managing discharge from measures ‘managing discharge from detention basins in accordance to detention basins in accordance to natural runoff’, or ‘water management in natural runoff’, or ‘water management in collaboration with power plant’ to collaboration with power plant’ to ‘master-planning advices for the ‘master-planning advices for the catchment area’catchment area’

sediment balance: sediment balance: • sediment traps, such as sediment sediment traps, such as sediment

ponds, ponds, • check dams for sediment control check dams for sediment control • the management of construction the management of construction

sites (temporary runoff diversions sites (temporary runoff diversions and chutes)and chutes)

7. 7. Rehabilitation techniques – Hydrology and Rehabilitation techniques – Hydrology and HydrodynamicsHydrodynamics

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Managing w ater w ithdraw el & adapting thedischarge regime to a less disturbed situation

Enhancement of base f low through stormw aterinfiltration

Measures to establish a less disturbed sedimentbalance

7. 7. Rehabilitation techniques – Hydrology and Rehabilitation techniques – Hydrology and HydrodynamicsHydrodynamics

Longitudinal m.:Longitudinal m.:

• Alignment and meanderingAlignment and meandering

• Biological continuityBiological continuity

Techniques for longitudinal, vertical and lateral Techniques for longitudinal, vertical and lateral connectivity 1connectivity 1

MeasuresMeasures::• drops were removed, drops were removed, ground ground

rampsramps, , fish ladders, fish ladders, daylightingdaylighting

7. 7. Rehabilitation techniques – Improving ConnectivityRehabilitation techniques – Improving Connectivity

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Removal & bypassing of structural f low and migrationbarriers (dams, w eirs, steps)

Bypassing ecologically poor river sections

Construction/ modif ications of damming and/orretaining structures

Restoration of the river gradient

Restoration of stream alignment (according channeltype)

Day lighting of streams

• pool and riffle zones were madepool and riffle zones were made

• Gravel beds and current deflectors Gravel beds and current deflectors have been successfully re-have been successfully re-introduced introduced

Vertical Vertical m.:m.:

• BedformBedformss

Techniques for longitudinal, vertical and lateral Techniques for longitudinal, vertical and lateral connectivity 3connectivity 3

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Inf ill or/and cleaning of river bed sediments Removal of hard bed lining re-establishing the

connection to ground w ater body

8. Summary8. Summary• Most projects occur on streams and Most projects occur on streams and

small riverssmall rivers

• Low number of completed urban Low number of completed urban rehabilitation schemes rehabilitation schemes

• Ecological aspects play an increasing Ecological aspects play an increasing role role

• Social aspectsSocial aspects

• Wide variety of soft techniquesWide variety of soft techniques

• Scarce use of evaluation methodsScarce use of evaluation methods

• Schemes need systematic Schemes need systematic performance controlperformance control

URBAN STREAM REHABILITATION. CASE STUDIES Contents: 1Approach 2Case studies 3Impacts of urban river...

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