Knet No: 10322417Transport Services Division
ROAD DESIGNStandards & Guidelines
DESIGN DEPARTURE/ EDD FORM APPLICATION
DOCUMENT AMENDMENT RECORD
Rev Change Description Date Prepared Reviewed Authorised
1 Initial Issue 18/08/18Joanna Davies /
Edi WinklerJoanna Davies /
Edi WinklerAna Glavinic
(Manager Technical Services)
To be read in conjunction with DPTI Design Departure / EDD Procedure Internal location Knet# 12971461External location https://www.dpti.sa.gov.au/standards/roads-all
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DESIGN DEPARTURE / EXTENDED DESIGN DOMAIN APPLICATION FORM
KNET FILE NO: #
PROJECT: PROJECT NAME
LOCATION: Identify the location of the proposal, e.g. street name(s), area, suburb/town
PROPOSED BY:Name: Date:
Position:
The documentation and process of seeking and obtaining endorsement and approvals remains the responsibility of the proposer.
This process for completion of this form is outlined in the “Design Departure / EDD Form Procedure”, refer kNet# 12971461
To be read in conjunction with DPTI Brownfield / Greenfield Guideline Knet# 12986288
This application form is to be used to ensure that all reasonable steps have been undertaken to achieve Normal Design Domain (NDD) prior to the consideration of E x t e n d e d D e s i g n D o m a i n ( EDD). NDD criteria should be applied where possible. If site constraints restrict the upgrade of the existing geometric alignment with normal design domain standards, and acceptable operational and safety levels can be maintained, the use of EDD can be considered as part of the upgrade works. The use of EDD is limited to only one design element and must be accompanied with an off-set element designed above minimum NDD. This form provides technical approval of the design only. Final approval of installation/construction of design remains with the Project Manager/Sponsor. This form can be applied to NDD and other non-standard applications where applicable.
General principlesEDD is only applicable if any of the following apply:
There are significant controls/constraints on the site. Significant investment would be required to ameliorate the constraint and it is unjustifiable in the scope of works. The existing facility is likely to have been designed to a lesser standard. There is no accident/crash history or operational problems associated with the site, relating to the EDD parameter under
consideration.
Information provided in support of this EDD should, where possible, limit the use of jargon and be in plain English.
Extended Design Domain must be applied at the scoping stage only.
CONSULTATION
Discipline Reviewer Comments Date
Road & Marine Assets
Field Services
Traffic Operations
Safety Strategy
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Technical Services
PROJECT MANAGER COMMENTSAny further considerations that should be considered when reviewing and/or approving the proposed use of EDD.
CERTIFICATIONIn compliance with reasonable engineering principles, I consider the technical mitigating treatments appropriate and the decision to adopt this EDD as acceptable, subject to any conditions below.
Name
PRINCIPAL ROAD DESIGN ADVISORSignature Date:
**Following approval, a copy of this form and supporting documentation, must be forwarded to the Manager Technical Services, DPTI.**
TECHNICAL APPROVAL I approve the use of the mitigating treatments for this EDD in this project as detailed, subject to any
conditions outlined below.
I reject the use of the mitigating treatments and request further consideration.
I endorse
Name:
MANAGER, TECHNICAL SERVICES
Signature: Date:
APPROVAL I approve
I rejectName:
COMMISSIONER OF HIGHWAYS / DELEGATE
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Design Departure (DD) and/or Extended Design Domain (EDD)Application Form
(This section can be expanded to multiple pages to cover any discussions involved and attachments required.)
FOR EDD ALL SECTIONS SHOULD BE COMPLETED
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DETAIL THE PROJECT PROBLEM AND WHY DD or EDD IS BEING CONSIDERED.
Provide all relevant information on the project problem. Include details of the issue/s, data available, design criteria, crash statistics, cross sections, site constraints, speed, composition of traffic, traffic volumes, etc.
CLEARLY ARTICULATE IN DETAIL OPTIONS CONSIDERED TO ADDRESS THE PROBLEM.
Description of what is proposed. For EDD need to include both NDD and EDD options that were considered.
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THIS ASSESSMENT MUST BE DONE IN ACCORDANCE WITH DPTI RISK MANAGEMENT POLICY DP086.
DISCUSS THE IMPACT AND FEASIBILITY ON THE PROJECT OUTCOME OF THE OPTIONS IDENTIFIED IN ABOVE.
Cost & Time;Social, Environmental, Safety & Traffic; Maintenance. Use tables, charts, and drawings as appropriate to illustrate and clarify impacts. Document the risk assessment and apply mitigation mearsures and provide a risk rating (low, medium, high)
CLEARLY ARTICULATE IN DETAIL THE MITIGATION MEASURES TO ADDRESS THE PROBLEM WHEN APPLYING EDD.
Plain english description of what is proposed to address EDD. Describe (any) alternatives that were considered - were these based NDD values?
WHERE RISKS ARE IDENTIFIED AS EXTREME OR HIGH, A FORMAL DETAILED RISK ASSESSMENT SHALL BE UNDERTAKEN
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ING DETAIL PROPOSED MONITORING REGIME FOR THE DESIGN, POST CONSTRUCTION
To be provided only if deemed necessary by Principal Road Advisor. Should include Monitoring regime, Maintenance.
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OTHER RELEVANT INFORMATION
Description
**ATTACH RELEVANT PLANS, MAPS, PHOTOS, DRAWINGS**
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DESIGN DEPARTURE / EXTENDED DESIGN DOMAINAPPLICATION FORM - EXAMPLE
DESIGN DEPARTURE EDD
KNET FILE NO: #1122Ɛ34567
PROJECT: Honeysville Upgrade Project
LOCATION: Horizontal Alignment; Flanders Grove Extension
PROPOSED BY:Name: A Dogsbodie Date: 31 April 2017
Position: Departmental Project Representative
The documentation and process of seeking and obtaining endorsement and approvals remains the responsibility of the proposer.
This process for completion of this form is outlined in the “Design Departure / EDD Form Procedure”, refer kNet#12530809.
This application form is to be used to ensure that all reasonable steps have been undertaken to achieve Normal Design Domain (NDD) prior to the consideration of E x t e n d e d D e s i g n D o m a i n ( EDD). NDD criteria should be applied where possible. If site constraints restrict the upgrade of the existing geometric alignment with normal design domain standards, and acceptable operational and safety levels can be maintained, the use of EDD can be considered as part of the upgrade works. The use of EDD is limited to only one design element and must be accompanied with an off-set element designed above minimum NDD. This form provides technical approval of the design only. Final approval of installation/construction of design remains with the Project Manager/Sponsor. This form can be applied to NDD and other non-standard applications where applicable.
General principlesEDD is only applicable if any of the following apply: There are significant controls/constraints on the site. Significant investment would be required to ameliorate the constraint and it is unjustifiable in the scope of works. The existing facility is likely to have been designed to a lesser standard. There is no accident/crash history or operational problems associated with the site, relating to the EDD parameter under
consideration.
Information provided in support of this EDD should, where possible, limit the use of jargon and be in plain English.
Extended Design Domain must be applied at the reference design stage only.
CONSULTATION
Discipline Reviewer Comments Date
Road & Marine Assets Carrie Oakey No Objections from Asset Management. 23/05/2017
Field Services April Shauer Not applicable N/A
Traffic Operations Robin Banks
No objections30/05/2017
Safety Strategy Willie Everlearn No objections 09/05/2017
Technical Services Sue Purglew
As the EDD Element is related to road geometry, Project Technical Services has been consulted. General agreement with minor condition.
21/06/2017
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EXAMPLE
PROJECT MANAGER COMMENTSAny further considerations that should be considered when reviewing and/or approving the proposed use of EDD.
No further comments. The use of the EDD for this design element is supported when the operating speed of the road user is considered.
CERTIFICATION OF DESIGN DEPARTURE
I consider the technical mitigating treatments appropriate and compliant with reasonable engineering principles, and the decision to adopt this Design Departure/EDD is acceptable, subject to any conditions below.
Name Max Power
PRINCIPAL ROAD DESIGN ADVISOR
Signature Max Power Date: 24/06/2017
**Following approval, a copy of this form and supporting documentation, must be forwarded to the Manager Technical Services, DPTI. If the change is considered controversial or politically sensitive in nature, this should be noted to ensure form is elevated to CoH or delegate level**
TECHNICAL APPROVAL OF EDD I approve the use of the mitigating treatments for this EDD in this project as detailed, subject to any
conditions outlined below.
I reject the use of the mitigating treatments and request further consideration.
I endorse
Name: Russell Leeves
MANAGER, TECHNICAL SERVICES
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EXAMPLE
Signature: R. Leeves Date: 27/06/2017
APPROVAL (IF DEEMED NECESSARY)
I approve
I rejectName: Warren Peace
COMMISSIONER OF HIGHWAYS / DELEGATE
Signature: Warren Peace Date: 8/07/2017
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EXAMPLE
Design Departure (DD) and/or Extended Design Domain (EDD) Application Form
(This section can be expanded to multiple pages to cover any discussions involved and attachments required.)
FOR EDD ALL SECTIONS SHOULD BE COMPLETED
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DETAIL THE PROJECT PROBLEM AND WHY DD or EDD IS BEING CONSIDERED.
The Flanders Drive extension provides a link from the Flanders Medical Centre to Starling Road. Due to the constraints from the location of existing intersections, existing buildings and car parking facilities and the need to consider the future extension of the RaiLink line the horizontal radius of Flanders Drive extension is required to be reduced from the Normal Design Domain, the proposed alignment is shown in Figure 1.
Figure 1: Proposed 132.5m horizontal radius with adverse crossfall
CLEARLY ARTICULATE IN DETAIL OPTIONS CONSIDERED TO ADDRESS THE PROBLEM.
The following options have been considered;
1. Provide a 200m horizontal curve with adverse crossfall (NDD).
2. Change the road crossfall so that the curve is super-elevated (NDD).
3. Provide a 90m or greater horizontal curve (EDD).
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EXAMPLE
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THIS ASSESSMENT MUST BE DONE IN ACCORDANCE WITH DPTI RISK MANAGEMENT POLICY DP086.
DISCUSS THE IMPACT AND FEASIBILITY ON THE PROJECT OUTCOME OF THE OPTIONS IDENTIFIED IN ABOVE.
Option 1. Changing the horizontal alignment to achieve a 200m radius (see Figure 2 below).
In order to achieve a horizontal alignment with a 200m radius the road alignment would be required to be shifted further West (circa 5-10m). This is however considered undesirable as;
It reduces the available development space to the West and increases the ‘dead’ space to the south of the corridor.
It increases the interface of the potential rail alignment with the road alignment. The below sketch shows the likely interface between Flanders Drive Extension and the RaiLink alignment based on the 15% concept design.
In Figure 2 the 200m horizontal design is indicated in green, the red lines show how the Northern shared path would be required to be realigned. The magenta lines show the required stopping sight distance and safe intersection sight distance associated with the greater 200 radius, this is undesirable as it further restricts the sight line due to the likely pier locations for RaiLink.
Figure 2: 200m horizontal radius curve overlay
Option 2. Change the road crossfall so that the curve is super-elevated.
Altering the crossfall to produce a super elevated curve leads to an increased extent of works on Other Drive and Another Avenue including, changes to drainage patterns and property access arrangements. Consequently, increasing disruption for stakeholders and project costs.
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Stopping Sight Distance
Potential RaiLink Alignment
Safe Intersection Sight Distance
EXAMPLE
Option 3. Provide a 90m or greater horizontal curve on adverse crossfall (EDD);
A horizontal radius of 132.5m on adverse crossfall can be achieved and is considered the most optimal design achievable whilst providing;
An appropriate integration of the Flanders Drive Extension and the future RaiLink Good use of the available land and minimises wasted verge space
CLEARLY ARTICULATE IN DETAIL THE MITIGATION MEASURES TO ADDRESS THE PROBLEM WHEN APPLYING EDD.
Flanders Drive Extension has been designed to a design speed of 60km/h (posted 50km/h). The use of Normal design domain criteria requires a horizontal curve of 200m radius for adverse crossfall at 60km/h design speed. Under extended design domain the horizontal radius may be reduced to 90m (Austroads Part 3 table 7.10).
The close proximity of signals at each end of the Flanders Drive Extension will keep the operating speed of traffic at or below 50km/h within this area.
A horizontal curve has been designed with an optimal 132.5m radius, which is suitable for an operating speed of 50km/h using Normal Design Domain and is also greater than the Extended Design Domain value for a 60km/h design speed, as per Austroads table 7.10
WHERE RISKS ARE IDENTIFIED AS EXTREME OR HIGH, A FORMAL DETAILED RISK ASSESSMENT SHALL BE UNDERTAKEN
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DETAIL PROPOSED MONITORING REGIME FOR THE DESIGN, POST CONSTRUCTION
None
SEC
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C. OTHER RELEVANT INFORMATION
None
**ATTACH RELEVANT PLANS, MAPS, PHOTOS, DRAWINGS**
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(NDD) (EDD)
EXAMPLE