Norfolk Vanguard

The views expressed in this page do not represent those of the Planning Inspectorate. This page consists of content submitted to the Planning Inspectorate by the public and other interested parties, giving their views of this proposal.

Norfolk Vanguard

Received 10 September 2018
From Norfolk County Council

Representation

Norfolk County Council Comments on the Norfolk Vanguard offshore Wind Farm and Onshore Supporting Infrastructure
7 September 2018

Norfolk County Council:
(a) Supports the principle of this offshore renewable energy proposal, which is consistent with national renewable energy targets and objectives, subject to:
1. The holding highway objection set out in the report being satisfactorily resolved;
2. The implementation of appropriate highway; historic environment; and surface water conditions / requirements being resolved through the DCO; and
3. The detailed comments set out in this report and in the Appendix (below) being addressed through the DCO process.
(b) Supports the use of HVDC technology which removes the need for an additional HVAC Booster / Cable Relay Station near Happisburgh.

1. Substantive Comments
Overview Comments
1.1. The principle of this offshore renewable energy proposal is supported as it is consistent with national renewable energy targets and objectives, subject to the detailed comments below being satisfactorily resolved with the applicant.
Grid Connection Issues
1.2. Comment - the County Council welcomes the decision by Vattenfall to pursue a HVDC solution which removes the need for additional onshore infrastructure (cable relay station) in North Norfolk and reduces the potential environmental impact associated with the cable route by narrowing the cable corridor from 100m to 45 m.
Electricity Supply Issues
Comments
1.3. It is felt that Vattenfall should work with National Grid and UK Power Networks to consider options regarding the potential to feed electricity into the local transmission networks.
In addition the County Council will continue to work with the Local Enterprise Partnership (LEP) through the TRI - Local Energy Strategy (endorsed by this Committee in July 2018), in order to lobby central government to make legislative changes to overcome the obstacles to secondary inter-connection raised above.
Socio-Economic Issues
Comments
1.4. The County Council should continue to work pro-actively with Vattenfall to demonstrate the economic benefits of using the Port facilities at Great Yarmouth for:
• Construction; assembly and manufacture of windfarm components; and
• Operations and maintenance.
The County Council should also continue to work with the applicant to develop the creation of apprenticeships; work experience; and internships.

Wider Community Issues and Impact on Business
Comment
1.5. The County Council welcomes the commitment towards establishing some form of community benefit and would ask Vattenfall to ensure all stakeholders/communities are made aware of such funds and have the opportunity to make appropriate bids.
1.6. The reduction in the potential impacts and disruption to business as a consequence of using HVDC technology is welcomed, however, it is felt that Vattenfall should commit to providing appropriate compensation for businesses and communities adversely affected by the construction works.
Commercial Fishing
Comment
1.7. The County welcomes the revised/amended design of the above proposal and mitigation measures set out in the applicant’s ES. However, where there is likely to be a demonstrable impact (i.e. during: construction; operation and/or decommissioning) on commercial fishing affecting communities in Norfolk, it is considered that Vattenfall should provide appropriate compensation (i.e. disturbance payments) to those fishing businesses affected. It is understood that Vattenfall are prepared to provide compensation in appropriate circumstances.
Local Highway - key Issues
Comment
1.8. It is felt that the applicant needs to find a different site for their main compound. However, if they wish to pursue their chosen site then they will need to:
(i) provide a scheme of permanent off-site highway improvement works comprising carriageway widening along the entire route from the compound to the main road; and
(ii) demonstrate that such a scheme is capable of overcoming the issues previously identified by PINS.
In the meantime it is felt that a holding objection on highway safety grounds should be raised to the inclusion of this site.

1.9. At the time of writing this report the County Council’s highway officers are still carefully assessing the supporting documentation in respect of the above matters and will make appropriate comments under delegated officer powers and feed these back to the Planning Inspectorate within the prescribed consultation period. This may include, where appropriate:
(a) Raising any necessary holding highway objection in the event that highway safety is deemed to be compromised; and/or
(b) Seeking Planning Conditions (Requirements) to be attached to the DCO in order to overcome any highway issue.

Wider Strategic Highway Issues
Comments

1.10. (a) Vattenfall need to satisfy Highways England with regard to the safety of their proposed access at Necton onto the A47(T). Impact upon driver delay along the trunk road network will also be assessed by Highways England.

(b) Vattenfall should work closely with Highways England and Norfolk County Council (Highway Authority) to ensure the proposed cable route does not fetter any future plans for the dualling of the A47(T);

(c) Vattenfall are asked to ensure that their underground Cable Route does not fetter any future highway improvement schemes in Norfolk and that where any reinforcement or diversion is needed to the cable route as a result of such highway works, that Vattenfall will be responsible for any upgrades or diversion of the cables and will fully meet the costs of these works.
Minerals and Waste
Comment
1.11. Norfolk County Council in its capacity as the Minerals and Waste Planning Authority does not object to the Proposed Vanguard Wind Power Project provided that the applicant continues to work with Norfolk County Council regarding the mitigation of impacts on the Mineral Safeguarding Areas.

Flood and Drainage Issues and Comments
Comment
1.12. The LLFA welcomes that sustainable drainage systems (SuDS) have been proposed for the project where permanent above ground infrastructure is proposed to mitigate against additional impermeable surfaces creating an additional risk of flooding. The LLFA have considered the submitted documents and are pleased to see that strategies have been supplied for the sub-station and the National Grid sub-station extension study areas. The cable corridor has not been considered in the post construction drainage strategy due to the fact that the cable would be below ground and reinstatement to pre development state would mitigate the potential for increased runoff.

1.13. It is noted that Greenfield run-off rates and volumes have as yet to be agreed with the LLFA. This will need to be considered during detailed design stage.

1.14. It should be noted that where ordinary watercourses are to be crossed by open cut, or any other temporary works are proposed as part of this project are likely to affect flows in an ordinary watercourse, then the applicant would need the approval of Norfolk County Council. The County Council would appreciate early consultation on the number of such crossings of Ordinary Watercourses and the required timeframes for approval. This will enable the team to have adequate staffing resources in place to ensure approvals are not unduly delayed and for and issues to be identified. It should also be noted that other ordinary watercourse crossings would need consent approval from the relevant Internal Drainage Board (IDB). In line with good practice, Norfolk County Council seeks to avoid culverting, and its consent for such works will not normally be granted except as a means of access. Such approvals are separate from planning and temporary mitigation methods may be required while cable laying is undertaken.

1.15. Norfolk County Council appreciates that these are initial drainage proposals, however, ideally these matters above (covering infiltration testing and drainage design) should be clarified prior to determination, to ensure that the site has a deliverable surface water drainage strategy. In particular there is no maintenance or management strategy supplied with the application and the LLFA have had to assume that the applicant will take responsibility for maintaining the drainage for the lifetime of development. The LLFA recognise this is a strategic application and is being determined by the Secretary of State as the Planning Authority and to ensure the best possible drainage strategy is developed Norfolk County Council would ask that the attached condition / requirement (see Appendix 1) is integrated into any final DCO consent. Additional technical LLFA will be sent under delegated officer powers to the Planning Inspectorate along with the above comments.

Landscape
Comments
1.16. It should be noted that landscape issues are ultimately a matter for Breckland District Council to comment on as the Local Planning Authority with their own adopted Local Plan policies covering landscape and other environmental matters.

1.17. While it is accepted that the onshore elements of Norfolk Vanguard have the potential to impact the landscape and visual amenity, measures have been “designed-in” to minimise these impacts. It is also noted that the location chosen has been selected to minimise visual impact, particularly in relation to the Substation and the National Grid Substation Extension, where existing vegetation and landform have been used to intercept views.

1.18. The decision by Vattenfall to pursue a HVDC option in terms of its cable route has, as indicated above, taken away the need for a cable relay station / booster station close to the Norfolk Coast (near Happisburgh). This option is welcomed in terms of minimising the impacts of this development on the landscape in North Norfolk.

Public Health
Comments
1.19. The County Council would expect detailed matters relating to, for example construction noise; local environmental health; and any other potential contamination issue, to be addressed by the relevant District Councils and/or other statutory body such the Environment Agency. Providing the District Councils are satisfied with the proposal in relation to the above matters, the County Council would not wish to raise any public health concerns at this time.




Appendix
Response to Norfolk Vanguard DCO Application -
Detailed Comments

Public Rights of Way
1.20. It is noted that the onshore cable route intersects with Public Rights of Way (PRoW), including National and County Trails, at 45 locations. Mitigation for impacts on users of the PRoW network is in the form of embedded (‘designed-in’) mitigation and method statements.
Comment
1.21. Norfolk County Council welcomes the use of HDD underneath some of the particularly heavily-used recreational routes (long-distance trails), particularly at landfall where the cables will intersect with the England Coast Path. HDD is also proposed for cable-laying across two further Trails managed by Norfolk Trails, namely Marriott’s Way (twice) and Paston Way (both these sites are also designated County Wildlife Sites at the crossing points). This approach should result in negligible disruption to users of these Trails. It is noted that HDD is not proposed at the crossings of two further Norfolk Trails, the Wensum Way and Weaver’s Way, nor the majority of the crossing points of the general PRoW network.

1.22. Mitigation for impacts on the majority of the PRoW and Trails network will be addressed by two documents: A Public Right of Way Strategy, and a Code of Construction Practice (CoCP), draft versions of which have been submitted with the DCO application. The Council believes these documents should result in appropriate measures to manage impacts in relation to cable-laying. In relation to the discharge of the DCO requirement for the CoCP, the documents refer to liaison with the “relevant local planning authority” (e.g. CoCP, section 4; paragraph 71; p 16). However, when it comes to matters relating to PRoW and Trails, it is felt that the County Council as the Highways Authority should be the relevant local authority to agree the management of PRoW.
1.23. The County Council welcomes the intention of the applicant to liaise with the PRoW Officers and Trail Officers over short-term temporary diversions of PRoW or other potential impacts. This will be important in reducing the burden on NCC in managing matters relating to the PRoW network with regards to the cable-laying works. The County Council also welcomes the approach for providing advanced warning of works that would affect PRoW. Where Norfolk Trails would be affected, it would additionally be helpful if information could be provided for inclusion on the Norfolk Trails website.

Ecology
1.24. The involvement of the County Council with regards to ecology has been with onshore works only. Representatives from the Natural Environment Team have been involved in the onshore Ecology Expert Topic Group (ETG).

1.25. The Ecology Chapter of the ES (Chapter 22) and the onshore Ornithology Chapter (Chapter 23) describe the ecological baseline and assess the impacts resulting from the onshore infrastructure requirements. The design of the scheme contains “embedded mitigation” for ecology. Where “additional mitigation” is required, potential impacts on terrestrial ecology will be delivered as described in the Outline Code of Construction Practice (OCoCP) and the Outline Landscape Ecological Management Strategy (OLEMS). The final detail of the mitigation and enhancement measures will be provided through one or more Ecological Management Plans (EMP) which will act as a single document for all ecological mitigation considerations on site.
Comments
1.26. The County Council welcome the above approach and agree the content of the outline CoCP and the OLEMS. In the second document, it is stated that “Norfolk Vanguard Limited will work with the relevant local authorities to ensure appropriate resourcing is in place to monitor compliance with the provisions of the OLEMS, and the plans and schemes of which it forms the basis”. The Natural Environment Team of the County Council would wish to be involved in this process.

1.27. The County Council welcomes the use of HDD where cable routes intersect with County Wildlife Sites. It is noted that a running track will still be necessary at the Wendling Carr CWS, but the need for this was discussed at the ETG meeting and is further described in the ES. The County accept that this approach is needed and believe the proposed mitigation is appropriate.

1.28. The County Council has previously raised concerns about the following matters, which have now been addressed:

• The constraints on access for ecological surveys: The OLEMS states that due to access constraints only 50% of the onshore project area was subject to ecological field surveys, and only 40% of the ponds. It is noted that the use of the Norfolk Living Map to ‘fill-in’ data gaps at this stage, but recognise field surveys of the currently un-surveyed locations will be necessary post-consent, and these surveys may lead to further mitigation at specific locations.
• Insufficient survey effort of CWS: At an early stage of the scoping process, the County Council advised that surveying of CWS close to the cable corridor was necessary (ETG meeting Jan 2107). This was accepted by Vattenfall and the surveys were completed. The results of those surveys are included in the ES.
• The suitability of the bat surveys to enable delivery of appropriate assessments of impacts and therefore appropriate mitigation (ETG Meeting July 2017): Vanguard came back to the County Council on this matter with revised reports, and the County Council is now satisfied that the assessments are broadly valid and the proposed mitigation for is appropriate. It is noted that some surveys will still need to be made post-consent at locations where access constraints resulted in no or incomplete surveys (OLEMS, paragraph 68). It is also noted that during the design process, landfall has moved away from the key area of concerns for barbastelle bats at the Paston Great Barn SAC colony.

Historic Environment
Onshore Comments
1.29. Subject to the submission and approval of a revised version of Document 8.5 Outline Written Scheme of Investigation: Archaeology and Cultural Heritage (Onshore) to state that work will be carried out in accordance with the Norfolk County Council Standards for Development-led Archaeological Projects in Norfolk (2018), the County Council is happy to recommend that the following requirements are placed on the consent if granted;

1.30. A) No development shall take place other than in accordance with the submitted and approved Outline Written Scheme of Investigation: Archaeology and Cultural Heritage (Onshore).

And, separately,

B) The development shall not be operated until the site investigation and post investigation assessment has been completed in accordance with the programme set out in the archaeological written scheme of investigation approved under (A) and the provision to be made for analysis, publication and dissemination of results and archive deposition has been secured.

Offshore Comments
1.31. The Offshore Historic Environment implications of the proposed development are considered in Chapter 17 of the ES (Offshore Archaeology and Cultural Heritage). The offshore historic environment below the low-water mark is not specifically within the remit of the County Council.

1.32. A decision has been made by Vattenfall to use a long HDD technique at the landfall of the cable route. As a result of this there will be no construction work, or resulting historic environment impact, within the inter-tidal zone on Happisburgh beach (where internationally significant archaeological remains of Palaeolithic date are known to exist). As such the County Council does not have any specific comments or recommendations to make on the offshore archaeology and cultural heritage of the proposed development. However, Vattenfall and their heritage consultants should continue to liaise with Historic England and other key stakeholders (e.g. Ancient Human Occupation of Britain) regarding any post-consent works.

Lead Local Flood Authority (LLFA) Comments
1.33. The ES states that the crossing of ordinary watercourses would be by Horizontal Directional Drilling (trenchless) or open cut. Referring to Appendix 20.4 Detailed Watercourse Crossing Schedule Table 20.1 it is noted that it appears that the majority all Norfolk County Council ordinary watercourses are proposed to be crossed by open cut rather than Horizontal Directional Drilling for permanent works. If this is the case, or any other temporary works proposed as part of this project are likely to affect flows in an ordinary watercourse, then the applicant would need the approval of Norfolk County Council. The County Council would appreciate early consultation on the number of such crossings of Ordinary Watercourses and the required timeframes for approval. This will enable the team to have adequate staffing resources in place to ensure approvals are not unduly delayed and for and issues to be identified. It is also noted that other ordinary watercourse crossings would need consent approval from the relevant Internal Drainage Board (IDB). In line with good practice, Norfolk County Council seeks to avoid culverting, and its consent for such works will not normally be granted except as a means of access. It should be noted that this approval is separate from planning and temporary mitigation methods may be required while cable laying is undertaken.

Proposed Condition/Requirement -
1.34. Prior to commencement of development, in accordance with the submitted Environmental Statement for Application for Development Consent - The proposed Norfolk Vanguard Offshore Wind Farm, detailed designs of a surface water drainage scheme incorporating the following measures shall be submitted to and agreed with the Secretary of State or his delegated approving body. The approved scheme will be implemented prior to the first use of the development. The scheme shall address the following matters:

I. Detailed infiltration testing to be undertaken in accordance with BRE Digest 365 within the study areas for the sub-station and the National Grid sub-station extension for the design of SuDs features.
II. If infiltration is not possible surface water runoff rates will be attenuated to the pre development 1 in 1 year rate (or 2 l/s/ha). Where applicable confirmation should be sought from the Internal Drainage Board that the proposed rates and volumes of surface water runoff from the development are acceptable.
III. Provision of surface water infiltration / attenuation storage should be sized and designed to accommodate the volume of water generated in all rainfall events up to and including the critical storm duration for the 1 in 100 year return period, including allowances for climate change, flood event.
IV. Detailed designs, modelling calculations and plans of the of the drainage conveyance network in the:
• 1 in 30 year critical rainfall event to show no above ground flooding on any part of the site.
• 1 in 100 year critical rainfall plus 40% climate change event to show, if any, the depth, volume and storage location of any above ground flooding from the drainage network ensuring that flooding does not occur in any part of a building or any utility plant susceptible to water (e.g. electricity equipment required at the converter / booster station and substation) within the development.
V. The design of any drainage structures will include appropriate freeboard allowances. Plans to be submitted showing the routes for the management of exceedance surface water flow routes that minimise the risk to people and property during rainfall events in excess of 1 in 100 year return period
VI. Details of how temporary works or temporary storage areas that will generate surface water runoff will be controlled to prevent a temporary increased risk of flooding. These details will also include what strategy/ plans will be provided to reinstate land to the pre-development state.
VII. Finished ground floor levels of the converter / booster station and substation should have a freeboard such that all infrastructure is above expected flood levels from all sources of flooding, including fluvial flooding associated with the ordinary watercourse, tidal flooding and any above ground storage or flooding from the proposed drainage scheme.
VIII. Details of how all surface water management features are to be designed in accordance with The SuDS Manual (CIRIA C697, 2007), or the updated The SuDS Manual (CIRIA C753, 2015), including appropriate treatment stages for water quality prior to discharge.
IX. A maintenance and management plan detailing the activities required and details of who will adopt and maintain the all the surface water drainage features for the lifetime of the development. This will also include the ordinary watercourse and any structures such as culverts within the development boundary.

Reason:
To prevent flooding in accordance with National Planning Policy Framework paragraph 103 and 109 by ensuring the satisfactory management of local sources of flooding surface water flow paths, storage and disposal of surface water from the site in a range of rainfall events and ensuring the surface water drainage system operates as designed for the lifetime of the development.

1.35. NB Further detailed technical comments will be sent to both the applicant and the Planning Inspectorate.



Additional LLFA Comments

Summary of Local Flood risks in the vicinity of the site

• The project has been split into study areas, Landfall – Onshore cable route including access routes and mobilisation areas, Onshore project substation and National Grid substation extension and overhead line.
• There are areas at risk of surface water flooding within the study area boundary 1 in 1000 (0.1% annual probability) flood event as shown in the Environment Agency’s Risk of Flooding from Surface Water (RoFSW) maps.
• The onshore project landfall, substation and National Grid substation extension are located in Flood Zone 1 of the Environmental Agency Flood Zone Risk Maps, which is classified as land with a low risk of flooding (less than 0.1% chance of flooding in any year). The majority of the onshore cable route is located within Flood Zone 1, however there are a number of locations at which the onshore cable route intersects areas of Flood Zone 2 and 3.
• The British Geological Survey (BGS) maps identify the bedrock underlying the onshore project area as Chalk to the west and Neogene and Quaternary Rocks to the east, overlain by superficial deposits of till (Diamicton), glacial sand and gravel, clay, silt and sand alluvium, and Crag Group (sand and gravel).
• A number of Source Protection Zones (SPZs) are identified within the onshore project area, with both inner and outer zones of the SPZ areas extending across the eastern section of the onshore cable route.
• No infiltration testing has been carried out at this stage. Geotechnical investigation should be undertaken to determine whether material on this site has infiltration potential in line with the SuDS hierarchy. This information should be representative of on-site conditions. If material is found to have infiltration potential, detailed infiltration testing should be undertaken in line with BRE 365 :
• The flood risk study areas include a number of catchments associated with EA designated main rivers and IDB/local authority ordinary watercourses including the River Bure catchment, the River Wensum catchment, and the River Wissey catchment. Mitigation measures have been identified including a commitment to trenchless crossing techniques for a number of sensitive watercourses, sediment management, construction drainage, and implementation of best practice measures.

• The flood risk study area crosses a number of existing field drains, ditches and irrigation channels which may require consents for works to ensure that any flood risk is not adversely affected.
• The site passes through the several IDB areas for the regulation of ordinary watercourses where consents may be required.
• There are no LLFA records of incidents of internal or external flooding on or adjacent to the study areas. However it should be noted that our records only cover the period of 2011 to the present day.

Summary of assessment of Flood Risk and submitted drainage proposals

The Flood Risk Assessment / Drainage submitted with the Environmental Statement, has been assessed against the National Planning Policy Framework (NPPF), Planning Practice Guidance, the SuDS Non-Statutory Technical Standards (NSTS) (March, 2015) and the policies of the adopted Norfolk Local Flood Risk Management Strategy as follows:
• The Environmental Statement has made an assessment of local flood risk issues and identifies all sources of risk for the main catchment areas and study areas, both during construction and the operation/maintenance of the scheme. It has also considered the cumulative effect of other proposed schemes.
• The Environmental Statement drainage strategy states that the SuDS discharge location hierarchy will be followed (soakaway testing will be carried out to determine the feasibility of infiltration or evidence for not discharging via infiltration).(Volume 2 Appendix 20.01 20.10.1 (194)). This should be demonstrated at detailed design.
• Greenfield run-off rates have as yet not been agreed with the LLFA. This will be required at detailed design.
• Post construction the controlled runoff rate will be equivalent to the greenfield runoff rate. The resultant storage / attenuation volume provided will be sufficient to ensure that during the 1 in 100 year event plus an allowance for climate change there will be no increase in runoff from the site.
• Description of SuDS component elements: It is stated that a pre-construction Surface Water and Drainage Plan will be developed, agreed with regulators and implemented to minimise water within the working areas, to ensure ongoing drainage of surrounding land and that there is no increase in surface water flood risk. This will assess the current and proposed runoff rates, volume of storage required and the proposed approach for discharge of water from the site. However no detail is currently provided in the ES. During construction, the cable route will be bounded by drainage channels (one on each side) to intercept drainage from within the working corridor. Additional drainage channels will be installed to intercept water from the cable trench. Where water enters the trenches during installation, this would be pumped via settling tanks or ponds to remove sediment, before being discharged at a controlled rate into local ditches or drains via temporary interceptor drains. Depending upon the precise location, water from the channels will be infiltrated or discharged into the drainage network. Some form on contingency plan will be required to be considered for any significant rainfall event. Post construction the surface water drainage requirements for the National Grid substation extension and onshore project substation will be dictated by the final Surface Water Drainage Strategy. Changes in surface water runoff as a result of the increase in impermeable area from the onshore project substation and National Grid substation extension will be attenuated and discharged at a controlled rate equivalent to the greenfield runoff rate. The resultant storage / attenuation volume provided will be sufficient to ensure that during the 1 in 100 year event plus an allowance for climate change there will be no increase in runoff from the site. An attenuation pond with a volume of 4,050m3 (approximate dimensions of 58m x 58m x 1.2m) has been allowed for at the onshore project substation to provide sufficient attenuation to greenfield runoff rates into the closest watercourse or sewer connection. The full specification for the attenuation pond should be addressed as part of the detailed design.
• Trenchless crossings are to be used at key watercourse crossing locations. At other crossing locations it is proposed that open cut techniques are utilised to cross the watercourse.
• The applicant has not identified exceedance routes for flows in excess of a 1 in 100 year rainfall event. This will be expected at detailed design stage. Consideration should be given to the expected depth/velocity of flood water to quantify any potential risks to people and property in the event of exceedance of the drainage inlets. This should be provided at detailed design.
• A maintenance plan has not been submitted as part of the DCO at this stage. Consideration needs to be given to the ongoing management and maintenance of all drainage features over the lifetime of the development. A maintenance plan identifying the required actions and responsible owners should be submitted to ensure that all parties understand their responsibilities. This includes all drainage infrastructure, such as pipes and tanks, permeable paving within the curtilage of the station sites, as well as the ordinary watercourse and any structures such as culverts within the development boundary. We recommend that further information is requested.


Summary of alignment to relevant Non-statutory technical standards for sustainable drainage systems

S2 . The FRA states that the post development 1:1 year run off rates will be equal to the calculated greenfield rates for the sub-station sites. This should be determined during detailed design.
S4/S6 – The information provided indicates that runoff volumes will not increase post-development by limiting to 2l/s/ha or QBAR whichever is the greatest. This should be maintained during detailed design.
S7 – The FRA does not include calculations to show that there will be no flooding on site from the proposed drainage scheme for the 1:30 plus climate change rainfall event.
S8 – At this stage the FRA does not state what protection will be provided to prevent flooding of any utility plant (e.g. sub station electrical infrastructure) during the 1 in 100 year rainfall event. Essential equipment throughout the sites is recommended to be set above the anticipated flood levels to ensure that the substation operates during a significant rainfall event.
S9 – At this stage the FRAs have not identified exceedance routes for flows in excess of a 1 in 100 year rainfall event. Consideration should be given to the expected depth/velocity of flood water to quantify any potential risks to people and property in the event of exceedance of the drainage inlets. This will be expected at detailed design stage.


Additional Comments agreed at Norfolk County Council’s Environment, Development and Transport Committee on 7/9/18:

(a) Hedgerow

Comment - The County Council would ask that maximum possible replanting / mitigation of hedgerows is undertaken after works are carried out in respect of the cable route and any other onshore development resulting in the potential removal of hedgerow.

(b) Coastal Erosion

Comment – The County Council would ask that sufficient safeguards and mitigation measures are put in place where the offshore cable route makes landfall to the south of Happisburgh (as a planning requirement), in order to ensure the onshore infrastructure does not exacerbate existing coastal erosion in the area.

(c) Highway Access

The County Council will address all local highway issues arising from construction by seeking suitable planning requirements (conditions), in particular with regard to updating the outline Construction Traffic Management Plans. In addition the County Council will expect the developer to:
(A) enter into a legal agreement with the Highway Authority to ensure any damage is rectified;
(B) set up local stakeholder involvement group/s to enable any traffic issues arising during the construction phase to be discussed and resolved.