Chapter 13 Road Drainage and the Water Environment Document Reference MNB Part 6.1.14 Regulation Reference 5(2)(a) PINS Reference Number TR010010 AECOM A1-SENSLR: MNB – Environmental Impact Assessment – Volume 2: Environmental Statement 13-2 Chapter 13 Road Drainage and the Water Environment Introduction 13.1 This Chapter presents the assessment of the proposed bypass on the water environment. This includes a consideration of the potential effects on surface water quality, hydrogeology and flood risk. It sets out the environmental baseline, describes the scope and assessment methodology, presents the findings of the assessment, of likely effects for the construction and operation phases and any mitigation measures that have been taken into account. 13.2 Part 3 of the ES contains the following supporting information: Appendix 13.1 Legislation, Planning Policy and Scoping Consultation; Appendix 13.2 Surface Runoff Assessment (Method A), Groundwater Assessment (Method C), and Spillage Risk Assessment (Method D); Appendix 13.3 Hydrological Analysis and Hydraulic Assessment (Method E and F); Appendix 13.4 Baseline Data; Appendix 13.5 Environment Agency Flood Map; Appendix 13.6 Routine Runoff and Spillage Risk – Summary of Results; and Appendix 13.7 WFD Programme of Measures. Legislation and Planning Policy Legislation 13.3 The following lists European and National Legislation relevant to this study. More detail is provided in Appendix 13.1. European o Groundwater Directive (1980/68/EC) (to be repealed 2013)1; o Water Framework Directive (2000/60/EC); o Groundwater Daughter Directive (2006/118/EC, replacing 1980/68/EC)); o Environmental Liability Directive (2004/35/EC); o Fish (Consolidated) Directive (2006/44EC, replacing 78/659/EC)1; o Nitrates Directive (91/676/EC) o Dangerous Substances Directive (76/464/EC)1 o Dangerous Substances Directive (2006/11/EC replacing 76/464/EC)1;and o Priority Substances Directive (2008/105/EC). National o The Environmental (England and Wales) Permitting Regulations 2010; o The Flood and Water Management Act 2010; o The Planning and Compulsory Purchase Act 2004; o The Water Act 2003; o The Water Resources Act 1991; o The Land Drainage Act 1991 (as amended); o Part IIA of The Environmental Protection Act 1990; o The Town and Country Planning Acts and Regulations (various dates). 1 To be repealed by the WFD when fully implemented AECOM A1-SENSLR: MNB – Environmental Impact Assessment – Volume 2: Environmental Statement 13-3 o The Water Environment (Water Framework Directive) Regulations 2003; o The Control of Pollution (Oil Storage) (England) Regulations 2001; o The Conservation of Habitats and Species Regulations 2010; and o The Groundwater (Water Framework Directive) Direction 2006. Planning Policy 13.4 The Government’s water strategy for England, Future Water, was published in February 2008. This strategy sets out the Government’s long-term vision for water and the framework for water management in England. 13.5 The National Planning Policy Framework (NPPF) (March 2012) replaces existing national planning policy adopted since 2004 (e.g. Planning Policy Statement (PPS) 23 and PPS25). In particular, Section 11 Conserving and Enhancing the Natural Environment paragraph 109 states that development should be prevented from contributing or put at unacceptable risk from, or being adversely affected by unacceptable levels of water pollution. Section 10 Meeting the Challenge of Climate Change, Flooding and Coastal Change paragraphs 94 and 99 emphasise the need to adopt proactive strategies to mitigate and adapt to climate change over the long term, taking into account flood risk. 13.6 Local Planning Policy is set out by NCC using the former Castle Morpeth Local Plan, adopted in February 2003 as a guide for the time being. Policy RE4 Water Quality states that the Council will resist development which may adversely affect the quality of surface, underground or coastal water. Furthermore, any initiative to improve surface or coastal water quality will be encouraged. Policy RE5 Surface Water Run-Off and Flood Defences, prevents development in flood risk areas, or where development may increase the risk of flooding somewhere else, unless it falls into an exception category. In Castle Morpeth, however, because of geological conditions the safeguarding of ground water resources is not seen as an issue requiring formal policies, though the Council subscribes to the objective of the protection and efficient use of water supplies. In particular, water quality may be affected by emissions of water which has passed through old mine workings and been contaminated. Policy RE8 dealing with Contaminated Land is considered in Chapter 14 Geology and Soils. More detail on these policies is presented in Table 13.1.2 in Appendix 13.1. Methodology Scope of Assessment 13.7 This assessment has been carried out in accordance with guidance in Volume 11, Section 3, Part 10 of the Design Manual for Roads and Bridges (DMRB) (henceforth referred to as HD45/09). This assessment has identified the potential effects on the water environment by assessing the likely effects of the proposed scheme during construction and operation. The effects of the proposed scheme have been assessed, taking into consideration the magnitude of the effect and the importance of the receptor. 13.8 There are four assessments (HD45/09 assessment reference is denoted in brackets): Effects of routine runoff on surface waters (Methods A and B); AECOM A1-SENSLR: MNB – Environmental Impact Assessment – Volume 2: Environmental Statement 13-4 Effects of routine runoff on groundwater’s (Method C); Spillage Risk Assessment (Method D); and Flood Effects (Methods E and F). 13.9 For the purpose of the surface water (water quality and flood risk) the study area includes all features within approximately 1km of the site boundary. However, watercourse flow effects may propagate downstream, thus where relevant this study has also considered a wider study area (up to 2km downstream of the site boundary). In addition, since flood risk can affect upstream and downstream areas, this study has also considered a wider study area, where relevant. 13.10 Effects on groundwater may be local or regional in scale, depending on the size and duration of the imposed stresses and properties of the hydrogeological regime. For example, local effects may occur in permeable drift deposits by lowering of the water table, which may be temporary through construction dewatering, or permanent by land drainage. Regional effects associated with roads may include groundwater pollution as a result of diffuse pollution from surface water road drainage, discharged to soakaway, to bedrock over many kilometres of road. The area of interest for local or temporary effects is considered to be within 1km of the road, whereas regional effects may occur at the scale of the total catchment area for a public supply well or the entire aquifer. 13.11 Development parameters as defined in Table 2.3 of Chapter 2, and their relevance in this assessment, are presented in Table 13.1. AECOM A1-SENSLR: MNB – Environmental Impact Assessment – Volume 2: Environmental Statement 13-5 Table 13.1 Development Parameters Is the information important in the assessment of If so how was the information included in the assessment, and in Development Parameter ‘likely significant effects’? Why? what form? Yes, the extent of the red line boundary defines the All watercourses within the red line boundary have been identified and Red Line Boundary area in which watercourses may be affected by the assessed. The potential affect of pollution on watercourses considers a scheme. study area that extends beyond the red line. Not directly. The vertical road alignment influences Vertical Road Alignment Please refer to the footprint of earthworks below. the size of earthworks, which is relevant. Watercourses tend to flow north-south and the proposed route is aligned Horizontal Road Yes, the horizontal alignment influences the broadly east-west, thus irrespective of the horizontal alignment, the same Alignment watercourses that are crossed by the scheme. watercourses are crossed. These crossings have been assessed in this chapter. Yes, the size of the road is relevant as this influences The number of lanes is fixed. The area of carriageway and the volume of Number of carriageways the volume of runoff and amount of vehicle derived traffic it is predicted to carry are data inputs to the assessment of routine pollutants that it will contain. runoff. No, the location of roundabouts is not a relevant Location of roundabouts No further comment. consideration for this assessment. Area of development See comment for ‘red line boundary’ above. No further comment. This chapter considers a range of mitigation measures to manage earthworks to prevent significant adverse effects on the water The volume of earthworks is relevant to the environment. The main risk is where earthworks are in close proximity to Volume of earthworks assessment of construction effects on watercourses watercourses. The detail of these measures will be developed by the (i.e. from silt laden runoff). Contractor during detailed design. The assessment is precautionary and has assumed a worst case, and an appropriate range of measures has been proposed. Appropriate measures have been proposed to manage earthworks close This is relevant to the assessment where earthworks to watercourses. Site specific measures will be determined by the Footprint of earthworks are close to watercourses.