Prior and currently considered bridge crossing at River Don on the Orange Route: EIR release

Information requested

You asked for:

“Please provide the following information whether data is held by Transport Scotland, its affiliates, contractors or their subcontractors.

For any prior (ie before October 2019) considered bridge crossings over the River Don on the Orange Route (FOI/19/02397)

For the currently (October 2019) considered bridge crossing the River Don on the Orange Route (FOI/19/02398)

1. A copy of the previous/current plans including elevations and sections,
2. Design documents available for the aforementioned design
3. Details of the footings in terms of size and depth which such footings are proposed to be sunk / installed.
4. An elevation drawing clearly showing a referenced river height and flood plain elevation
5. Any impact assessment / flood modelling which has been undertaken to determine the increase in flood risk to the Inverurie / Port Elphinstone areas as a result of installing such a bridge.
6. Advise whether such modelling includes 100 year flood data, 200 year flood data or a different duration.
7. Advise whether such modelling considers the effect of climate change and the resulting increased flood risk.
8. Advise whether such modelling considers the effect of developments upstream of the proposed bridge and the reduced ground absorption and higher run off rates which result.
9. Advise whether the flood modelling considers elevated levels in the River Don only, the River Ury only or both the rivers quantifying which worst case scenario has been considered.
10. Advise the number of houses and business which are modelled to be affected by the flooding event.
11. Provide the associated modelled flood map.
12. Provide details including maps of any flood alleviation features which are proposed to mitigate against flooding in the Inverurie and Port Elphinstone areas.
13. Advise whether the responsibility of maintaining such features will be the responsibility of Transport Scotland, or the local Aberdeenshire Council.
14. Advise whether and if so how including the output as to whether SEPAs Engineering in the Water Environment : Good Practice Guide : River Crossings was considered during the design or assessment of such a bridge.
15. Provide an estimate of construction cost for this bridge.”

Response

As all of the information you have requested is ‘environmental information’ for the purposes of the Environmental Information (Scotland) Regulations 2004 (EIRs), we are required to deal with your request under those Regulations. We are applying the exemption at section 39(2) of the Freedom of Information (Scotland) Act 2002 (FOISA), so that we do not also have to deal with your request under FOISA.

This exemption is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exemption. We have found that, on balance, the public interest lies in favour of upholding the exemption, because there is no public interest in dealing with the same request under two different regimes. This is essentially a technical point and has no material effect on the outcome of your request.

“Please provide…. 1. A copy of the previous/current plans including elevations and sections,”

I enclose the following Drawing as requested:

A96PEA-AMAR-HGN-SWI-DR-CH-335002 – Orange Route Plan and Profile Sheet 2 of 3

This Drawing reflects the design as shown at the Public Drop-in engagement events held in May 2019 and as noted on the Drawing, the route options and junction layouts will be subject to further development as we further progress the design and assessment of the scheme.

At this juncture of the A96 Dualling East of Huntly to Aberdeen Design Manual for Roads and Bridges (DMRB) Stage 2 route options assessment all structures are conceptual.

“Please provide…. 2. Design documents available for the aforementioned design, 3. Details of the footings in terms of size and depth which such footings are proposed to be sunk / installed. 4. An elevation drawing clearly showing a referenced river height and flood plain elevation”

With regards to your request for design documents, details of the footings and an elevation drawing of the bridge crossing over the River Don on the Orange route, an exception under regulation 10(4)(d) of the EIRs (unfinished or incomplete information) applies to the information you have requested because it is material which is still in the course of completion. The structures for each of the options under consideration on the A96 Dualling East of Huntly to Aberdeen scheme are currently being developed to an appropriate level of detail to inform the preferred route option decision expected to be announced and reported in a DMRB Stage 2 Scheme Assessment Report. Due to the number of responses received following the public engagement events held in May of this year, the work to identify a preferred option for the scheme might take until sometime next year to be completed. The structure type and span configurations of the preferred option once identified will be further developed during the DMRB Stage 3 assessment.

This exception is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exception. We have found that, on balance, the public interest lies in favour of upholding the exception. We recognise that there is some public interest in release as part of open, transparent and accountable government, and this will be met by the release of the DMRB Stage 2 Scheme Assessment Report in the coming months. However, this is outweighed by the public interest in ensuring that unfinished or incomplete information which is still being worked on is not disclosed when it might misinform the public.

“Please provide…. 5. Any impact assessment / flood modelling which has been undertaken to determine the increase in flood risk to the Inverurie / Port Elphinstone areas as a result of installing such a bridge.”

At this juncture of the A96 Dualling East of Huntly to Aberdeen Design Manual for Roads and Bridges (DMRB) Stage 2 route options assessment, the impact assessment / flood modelling which has been undertaken to determine any potential increase in flood risk to the Inverurie / Port Elphinstone areas as a result of installing such a bridge crossing the River Don on the Violet Route is ongoing, therefore an exception under regulation 10(4)(d) of the EIRs (unfinished or incomplete information) applies to the information you have requested because it is material which is still in the course of completion.

This exception is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exception. We have found that, on balance, the public interest lies in favour of upholding the exception. We recognise that there is some public interest in release as part of open, transparent and accountable government, and this will be met by the completion and release of the DMRB Stage 2 Scheme Assessment Report. However, this is outweighed by the public interest in ensuring that unfinished or incomplete information which is still being worked on is not disclosed when it might misinform the public.

Further explanation
All flood modelling carried out to date is based on models provided by Aberdeenshire Council.

It is recognised that the scheme traverses areas which are known to experience flooding and are identified by SEPA as being subject to flood risk. A key element of the design and assessment of each option is to ensure that existing flooding patterns are not made worse by the scheme. The flooding and drainage aspects of the scheme are being designed in consultation with SEPA and Aberdeenshire Council.

“Please provide…. 6. Advise whether such modelling includes 100 year flood data, 200 year flood data or a different duration. 7. Advise whether such modelling considers the effect of climate change and the resulting increased flood risk”

The flood modelling will cover the 200 year return period event, plus an allowance for climate change, as agreed with SEPA.

“Please provide…. 8. Advise whether such modelling considers the effect of developments upstream of the proposed bridge and the reduced ground absorption and higher run off rates which result”

Any developments upstream of the proposed bridge must adhere to current Aberdeenshire Council guidance, where surface water run off should be attenuated to a rate agreed with the Council as the Planning Authority. Any flood modelling in connection with the A96 Dualling East of Huntly to Aberdeen scheme will therefore assume the effect of the third party developments have been mitigated as necessary.

“Please provide…. 9. Advise whether the flood modelling considers elevated levels in the River Don only, the River Ury only or both the rivers quantifying which worst case scenario has been considered.”

The flood modelling will consider flows in both the River Don and the River Urie.

“Please provide…. 10. Advise the number of houses and business which are modelled to be affected by the flooding event. 11. Provide the associated modelled flood map.”

While our aim is to provide information whenever possible, in this instance the Scottish Government does not have the information you have requested in this part of your request. Therefore we are refusing your request under the exception at regulation 10(4)(a) of the EIRs. Under the terms of the exception at regulation 10(4)(a) of the EIRs (information not held), the Scottish Government is not required to provide information which it does not have. The Scottish Government does not have the information you have requested because, as advised above, all flood modelling carried out to date is based on models provided by Aberdeenshire Council.

This exception is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exception. We have found that, on balance, the public interest lies in favour of upholding the exception. While we recognise that there may be some public interest in the requested information, clearly we cannot provide information which we do not hold.

Further explanation
Please refer to Aberdeenshire Council for flood maps and the number of houses and businesses that may be at risk of flooding under a particular flooding event. Further information is provided at the links below.

http://www.inveruriefloodstudy.com/
http://www.inveruriefloodstudy.com/media/Presentations/Consultation2.pdf

As outlined above, a key element of the design and assessment of each option is to ensure that existing flooding patterns are not made worse by the scheme.

“Please provide…. 12. Provide details including maps of any flood alleviation features which are proposed to mitigate against flooding in the Inverurie and Port Elphinstone areas. 13. Advise whether the responsibility of maintaining such features will be the responsibility of Transport Scotland, or the local Aberdeenshire Council”

While our aim is to provide information whenever possible, in this instance the Scottish Government does not have the information you have requested in this part of your request. Therefore we are refusing your request under the exception at regulation 10(4)(a) of the EIRs. Under the terms of the exception at regulation 10(4)(a) of the EIRs (information not held), the Scottish Government is not required to provide information which it does not have. The Scottish Government does not have the information you have requested because any potential flood alleviation features or mitigation required will be developed during the DMRB Stage 3 Assessment, at which point the responsibility for maintenance can be determined.

This exception is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exception. We have found that, on balance, the public interest lies in favour of upholding the exception. While we recognise that there may be some public interest in the requested information, clearly we cannot provide information which we do not hold.

Further explanation
At this juncture of the A96 Dualling East of Huntly to Aberdeen Design Manual for Roads and Bridges (DMRB) Stage 2 route options assessment, while not associated to flood alleviation features it may help to explain that Sustainable Drainage Systems (SuDS) will be developed on this project to collect water from the new roads system.

SuDS are designed, constructed and maintained to be more sustainable than conventional drainage methods as they mitigate many of the adverse effects of storm water run-off on the environment by:

• Controlling the discharge rate to the receiving watercourse;
• Reducing pollutant concentrations in storm water;
• Acting as a buffer for accidental spills by preventing direct discharge of high concentrations of contaminants to the natural water course;

“Please provide…. 14. Advise whether and if so how including the output as to whether SEPAs Engineering in the Water Environment: Good Practice Guide: River Crossings was considered during the design or assessment of such a bridge.”

At this juncture of the A96 Dualling East of Huntly to Aberdeen Design Manual for Roads and Bridges (DMRB) Stage 2 route options assessment, the assessment of the route options is ongoing, therefore with regard to your request for whether and if so how including the output as to whether SEPAs Engineering in the Water Environment: Good Practice Guide: River Crossings was considered during the design or assessment of such a bridge an exception under regulation 10(4)(d) of the EIRs (unfinished or incomplete information) applies to the information you have requested because it is material which is still in the course of completion. The assessment of each of the options under consideration on the A96 Dualling East of Huntly to Aberdeen scheme is currently being developed to inform the preferred route option decision expected to be announced and reported in a DMRB Stage 2 Scheme Assessment Report.

This exception is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exception. We have found that, on balance, the public interest lies in favour of upholding the exception. We recognise that there is some public interest in release as part of open, transparent and accountable government, and this will be met by the release of the DMRB Stage 2 Scheme Assessment Report in the coming months. However, this is outweighed by the public interest in ensuring that unfinished or incomplete information which is still in being worked on is not disclosed when it might misinform the public.

Further explanation
The “Engineering in the water environment: good practice guide – River crossings”, is being considered during the DMRB Stage 2 Assessment as part of the route selection process. Please refer to the DMRB Stage 2 Early Sifting Reports and DMRB Stage 2 Pairing Assessments for further information on the route assessment process.

DMRB Stage 2 Early Sifting Reports
https://www.transport.gov.scot/publication/dmrb-stage-2-early-sifting-reports-east-of-huntly-to-aberdeen-a96-dualling/

DMRB Stage 2 Pairing Assessments
https://www.transport.gov.scot/publication/dmrb-stage-2-pairing-assessments-east-of-huntly-to-aberdeen-a96-dualling/

At this stage of the DMRB Stage 2 assessment, Section 4 of the SEPA “Engineering in the water environment: good practice guide: River crossings” is relevant.
(https://www.sepa.org.uk/media/151036/wat-sg-25.pdf)

“Please provide…. 15. Provide an estimate of construction cost for this bridge.”

With regards to the estimated construction cost for the bridge, an exception under regulation 10(4)(d) of the EIRs (unfinished or incomplete information) applies to the information you have requested because it is material which is still in the course of completion. The structures for each of the options under consideration on the A96 Dualling East of Huntly to Aberdeen scheme along with their estimated costs are currently being developed, in consultation with statutory bodies, to an appropriate level of detail to inform the preferred route option decision expected to be announced and reported in a DMRB Stage 2 Scheme Assessment Report in the coming months.

This exception is subject to the ‘public interest test’. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exception. We have found that, on balance, the public interest lies in favour of upholding the exception. We recognise that there is some public interest in release as part of open, transparent and accountable government, and this will be met by the release of the DMRB Stage 2 assessment report. However, this is outweighed by the public interest in ensuring that unfinished or incomplete information which is still in being worked on is not disclosed when it might misinform the public.

About FOI
The Scottish Government is committed to publishing all information released in response to Freedom of Information requests. View all FOI responses at http://www.gov.scot/foi-responses.

FOI/19/02397 - Information Released

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FOI/19/02398 - Information Released

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