Representation by Environment Agency (Environment Agency)
- Date submitted
- 18 July 2023
- Submitted by
- Other statutory consultees
Please find enclosed our relevant representation for the Bramford to Twinstead NSIP. The Role of the Environment Agency The Environment Agency is a statutory consultee on all applications for development consent orders. We have a responsibility for protecting and improving the environment, as well as contributing to sustainable development. We have three main roles: (i) We are an environmental regulator – we take a risk-based approach and target our effort to maintain and improve environmental standards and to minimise unnecessary burdens on business. We issue a range of permits and consents. (ii) We are an environmental operator – we are a national organisation that operates locally. We work with people and communities across England to protect and improve the environment in an integrated way. We provide a vital incident response capability. (iii) We are an environmental advisor – we compile and assess the best available evidence and use this to report on the state of the environment. We use our own monitoring information and that of others to inform this activity. We provide technical information and advice to national and local governments to support their roles in policy and decision-making. One of our specific functions is as a Flood Risk Management Authority. We have a general supervisory duty relating to specific flood risk management matters in respect of flood risk arising from Main Rivers or the sea. Overview and issues of concern Our relevant representation outlines where we consider further work, clarification or mitigation is required to ensure that the proposal has no detrimental impact on the environment. The design of the temporary bridges should allow unrestricted passage of wildlife. Without mitigation, the bridges may reduce connectivity of habitat up and downstream. Further advice can be found in section 1 of our response below. We also have concerns that the use of culverts will result in a temporary loss of habitat and affect the hydromorphology of watercourses. Further advice can be found in section 2 below. The temporary crossing of the Stour at Lamarsh will need to take into consideration the crossing of a flood embankment. It is our understanding that the proposals may have to take part of the embankment away to install a temporary bridge which we would advise against. Full comments are provided in section 11 below. Our full response can be found within our relevant representation below. Fisheries Biodiversity and Ecology 1.0 Document 2.11.13 Temporary bridges for access 1.1 The Design of bridges should be such that they allow unrestricted passage of wildlife and minimise the risks of pollution to the aquatic environment 1.2 In the absence of mitigation, the temporary bridges may reduce the connectivity of habitat upstream and downstream of the bridge. This could affect the movement of mammals, particularly otters, and make them vulnerable to death or injury due to collisions with vehicles using the access roads. Soil or other materials on the bridge surface could fall directly into the river causing pollution, or run-off from the bridge deck could find it’s way into the watercourse, causing an impact on water quality. 1.3 Bridges should be designed so that, from the top of the bank on each side of the river, there is a minimum of 3m width of natural land corridor between the bank top and the abutments of the bridge (this should be covered by Measure W17 of the CEMP). In addition there should be a minimum of 600mm clearance between the land surface at the bank top and the soffit of the bridge. The deck of the bridge should be designed so that there are no gaps through which material can fall, and the sides of the bridge should be shuttered to prevent material falling from the edges. In addition, a drainage system will need to be in place to prevent run-off from the bridge deck entering the watercourse. The latter point may be covered by measure GG15 of the CEMP. 2.0 Document 2.11.14 Temporary culverts for access 2.1 Culverting of watercourses will result in a temporary loss of habitat and affect the hydromorphology of watercourses 2.2 Culverting of watercourses will have a number of impacts, including direct loss of wetland habitat (in the footprint of the culvert), loss of longitudinal habitat connectivity and loss of width/depth variation. 2.3 Temporary bridges are preferable to culverts, as the impacts of bridges on riparian habitats and Water Framework Directive Hydromorphological Quality Elements will be lower than culverts. If culverts are to be used, there should be a firm commitment to remove these at the end of the construction period and to fully re-instate the watercourse. This should include the reinstatement of appropriate bed material, and a commitment that the restored sections of watercourse will have natural banks and not artificially reinforced banks. 3.0 Document 7.6.98 Overpumping during installation of open cut crossings and culvert installation. 3.1 Over pumping risks the entrapment or entrainment of fish present in watercourses. 3.2 Entrapment or entrainment can result in injury or death of fish, leading to direct impacts on biodiversity. 3.3 Overpumping in any watercourses that contain fish populations will require 2mm diameter screening of the pump intakes. This requirement should be satisfied by Measure B13 in the CEMP. Pollution Prevention 4.0 Document 6.2.9 ES Chapter 9 Water Environment 4.1 The document should be updated to define 'wastewater' referred to in paragraph 9.3.5. Uncontaminated rainwater may be discharged to land, but 'wastewater' may require an environmental permit. 5.0 Document 6.3.4.1 ES Appendix 4.1 Good Design 5.1 The application should consider sediment fencing adjacent to haul roads on slopes. 6.0 Document 7.5 Construction Environmental Management Plan 6.1 Please note that there is currently a large queue for permitting applications. We therefore recommend that the applicant submits their permitting application as soon as possible. 7.0 Document 7.5.1 CEMP Appendix A Code of Construction Practice 7.1 In relation to GG14 on page 4 - consideration must be given to any contaminated rainwater gathered in open-topped bunds - this will potentially need to be removed as hazardous waste. The use of covered or integral bunding will prevent this. 7.2 In relation to GG15 - we should be informed as soon as possible of any discharge of contaminated water in an emergency. 7.3 The applicant should define the type of pollution boom for W02. What sort of pollution could be expected? A boom will usually only provide limited containment of floating substances (such as oil boom in the case of most hydrocarbons). Groundwater and Contaminated Land 8.0 Document 6.2.4: Environmental Statement: Main Report Chapter 4 – Project Description 8.1 We refer to paragraphs4.4.64 & 4.4.65. We reiterate that the applicant should allow sufficient time for permit determination, there is a potential wait time and forward planning should prevent delays. 8.2 For paragraph 9.6.11, we are pleased that confirmation that hydrogeological risk assessments will be undertaken once the trenchless method has been confirmed - please engage early with the Environment Agency with this as to not cause any project delays. In section 10.4.38 it states "The hydrogeological risk assessment will be submitted to the Environment Agency for information prior to construction. " This should not be "for information" but submitted well in advance for approval to the Environment Agency. We need to review these documents well in advance of any works commencing. The same statement was repeated in Document 6.3.10.2: ES Appendix in relation to the Groundwater Baseline and Assessment in paragraph 3.4.13, so the same comments apply to this paragraph too. 8.3 It is worth noting that whilst open trenches are not anticipated to encounter groundwater in most cases, if they do and over a significant distance, it would be prudent to install clay barriers/stanks periodically in the trench to prevent a preferential pathway in the backfill media, which could potentially alter groundwater flow patterns. Flood Risk 9.0 Document 5.5 Flood Risk Assessment 9.1 We are satisfied with the documents that have been submitted in relation to flood risk. 9.2 The order of limits has been widened to accommodate soil storage outside of Flood Zone 3. 9.3 The trenchless crossings proposed advise that the drive pits will be located outside of Flood Zone 3 where practicable or would be managed in accordance with the flood risk action plan. 9.4 On receipt of a severe flood warning, the contractor would deploy suitable flood protection measures to safeguard work site personal and equipment. 9.5 Risk assessment and Method statements should be included in permit application. 9.6 Regarding the bridges and culverts the FRA confirms temporary bridges will be open span and 600mm above the 1:200 level, design drawings should be included in the permit application that show the proposed finished soffit level in m AOD for each bridge so it can be confirmed that the level is as agreed. Climate change does not need to be assessed as they are temporary. 10.0 Document 7.5: Construction Environmental Management Plan 10.1 The document confirms that there is no proposed temporary access route crossing over the Belstead Brook. Therefore, no culvert or bridge is anticipated. We believe other access crossing are non-main river and will be assessed by the Lead Local Flood Authority. 10.2 All temporary/enabling work is confirmed to be reinstated to original following completion of work. Flood Defenses/Maintenance 11.0 Document 7.5.1 CEMP Appendix A Code of Construction Practice 11.1 The temporary crossing over the River Stour at Lamarsh will need to take into consideration asset 148253 raised embankment, a bespoke design will need a permit. The applicant has mentioned some detail “W18 The temporary access route and underground cables will cross a flood defence embankment on the River Stour located off Bures Road (Grid reference TL 89599 36718). The crossing designs would avoid impacts on the defence foundations and construction works would be undertaken using methods that limit ground movement/settlement to reduce the potential to compromise the condition and stability of the embankment. In addition, in line with the requirements of the Environment Agency, should the potential for an impact to the flood defences be identified at the detailed design stage, then the flood defence would be monitored to establish a pre-construction baseline and for a period after completion of works to construct the crossings to enable detection of any effects on the structural integrity/condition of the assets during construction. The requirement for any such monitoring will be discussed with the Environment Agency as part of the application for a Flood Risk Activity Permit”. The applicant is not saying that the design will not affect the embankment at this stage. 11.2 It is our understanding that they may have to take part of the embankment away to install a temporary bridge as shown in the standard and we should advise them to avoid this. It is inherently important that the embankment and the flood protection is not affected. 12.0 Document 2.11.13 Design and Layout Plans Temporary Bridge for Access 12.1 The standard crossing design it does mention about navigation and the crossing over the Stour will have some effect on the navigation during construction/installation. Water Resources 13.0 We are pleased that the applicant has acknowledged that they may require abstraction licences. 14.0 In some sections they refer only to tankering in water, and in other places they speak about using the public water supply. East Anglia is a water stressed area and we have included further context in paragraphs 15 and 16 below. 15.0 The location of this development is in an area of serious water stress (as identified in our report Water stressed areas - final classification). We have evidence that indicates abstraction from groundwater to meet current needs of the population is already causing ecological damage to some Water Framework Directive (WFD) designated water bodies including chalk streams (where applicable) or there is a risk of causing deterioration to the ecology if groundwater abstraction increases. 16.0 Developments have the potential to increase demand for water and result in increased abstraction from groundwater sources. Anglian Water have recently published draft Water Resource Management Plans 2024 (WRMP24). Prior to alternative strategic sources of water becoming available in the long-term, water companies are proposing to help manage the risk of abstraction causing deterioration in status of WFD water bodies primarily through demand management measures such as leakage reduction and compulsory metering. The proposals set out in the Anglian Water draft WRMP24 mean we believe the company should be able to manage the risk of planned development and prevent overall increases in abstraction. Therefore we are not objecting to planning applications or NSIPs in this area. It should be noted that the water companies are heavily reliant on the success of demand management measures to maintain customer supplies until new strategic sustainable supplies of water can be developed. Any application should seek to achieve greater water efficiency and re-use in their designs wherever possible to help the companies meet their water efficiency targets. We have made representations on the water companies draft WRMP24 and will be working the water companies to ensure they address water resource pressures across East Anglia. 17.0 Overall, there is a large focus on mitigating against high flows and little addressing of things which may cause or impact lower flows. 18.0 We agree that there will be no likely significant effects on licence holders of abstractions resulting from the project once completed, but there is a risk that any changes to flow regime during the crossing of watercourses (by cable, or culvert) could impact abstractors (surface water as well as ground water), as they will have differing flow restrictions on their licence, thus if there is a decrease in flow caused by this process, it would be impacting the rights of licence holders. If there will be over pumping or similar in place and this will be designed to maintain the natural flow of the watercourse, then this could allay the concern (however, we would encourage communication with downstream licence holders for their information). If there is a risk that flows will be reduced it needs to be further considered and assessed and the abstractors need to be engaged with. There may be relevant agreements etc that need to be in place, as we cannot allow an activity to derogate those rights. 19.0 We note the application argues that tankering in the water reduces impacts on abstractors, which we don’t believe to be wholly true. Whilst it means that proposal won’t abstract from the river, downstream abstractors could still be affected by barriers created for construction. This should be assessed and mitigated for with the above in mind. 20.0 Furthermore, whilst the applicant has scoped in impacts on flows and hydrology, they have scoped out impacts on other abstractions – we would expect to see better justification for this as impacts on flows would be linked to impacts on abstractors. 21.0 Document 7.5.1 CEMP Appendix A Code of Construction Practice 21.1 There is a weighting heavily towards high flows here. The impact on low flows should also be considered in the river crossings and if it is appropriate to disturb the watercourse at times of low flow. Water Quality 22.0 Document 5.6 Water Framework Directive Assessment 22.1 We agree with the assessment. Good practice guidelines must be followed to ensure the risk to water quality is negligible. Especially with regards to soil and/or sediment entering the watercourse. 22.2 Section 4.2.3 mentions the WFD objective of achieving good status but does not mention the No deterioration objective of WFD. This should be amended or explained further as all water bodies require protection and all require no deterioration for water quality under WFD. 23.0 Document 6.2.9 ES Chapter 9 Water Environment 23.1 As noted in our response to document 5.6 Water Framework Directive Assessment above, this document again doesn’t mention the no deterioration portion of WFD. 24.0 Document 3.1 Draft Development Consent Order 24.1 The DCO doesn’t disapply the requirement for any environmental permit and no provision in the DCO overrides that. Permitting will be dealt with in the normal way and we flag to the applicant that they should apply for permits at their earliest convenience to avoid any delays. 24.2 The limits of deviation at Article 5 are quite extensive. We note that section a states that “the undertaker may deviate from the lines or situations of the authorised development shown on the work plans…”. We request to be notified of any situation where the location of river crossings or the method is changed. We also highlight that any change could impact on the necessity/type of permit application. We also note that section d states that “in respect of the underground electric line, deviate vertically.. ii) downwards to such extent as the undertaker considers necessary or convenient. The depth must be fully detailed in the hydrogeological risk assessment. We note that hydrogeological risk assessment will be submitted to the Environment Agency for information prior to construction. " This should not be "for information" but submitted well in advance for approval to the Environment Agency. We need to review these documents well in advance of any works commencing. These should include all of the relevant information in relation to depth to allow us to make a full judgement as to the suitability of the plans. 24.3 Article 50 concerns the temporary closure of, and works in, the River Stour. We are the navigation authority for the River Stour. Should the applicant require the use of a boat on the River Stour then a registration will be required to keep and/or navigate a boat on the Stour. Further information can be found here Anglian waterways: boat registration and application forms - GOV.UK (www.gov.uk). Navigation could be impacted by this article. Any closures of the navigation should be kept to an absolute minimum. Where this is unavoidable, we request to be consulted in advance so we can work with the applicant in order to minimise disruption. Yours faithfully Mr Liam Robson Sustainable Places - Planning Specialist