Tandridge District Council Water Cycle Study – Phase 3 Detailed December 2018 www.jbaconsulting.com Tandridge District Council Council Offices Station Road East Oxted Surrey RH8 0BT Water Cycle Study (Stage 3) 2018 i JBA Project Manager Alistair Clark 8a Castle Street Wallingford Oxfordshire OX10 8DL Revision history Revision Ref/Date Amendments Issued to V1.0 05/11/2018 Draft Report Mark Bristow V2.0 10/12/2018 Final Report Mark Bristow V3.0 10/12/2018 Final Report with amendments Mark Bristow from the Environment Agency Contract This report describes work commissioned by Tandridge District Council in February 2018. Tandridge District Council’s representative for the contract was Mark Bristow. Alistair Clark and Richard Pardoe of JBA Consulting carried out this work. Prepared by ............................... Richard Pardoe MSc MEng Analyst Reviewed by .............................. Paul Eccleston BA CertWEM CEnv MCIWEM C.WEM Technical Director Purpose This document has been prepared as a Final Report for Tandridge District Council. JBA Consulting accepts no responsibility or liability for any use that is made of this document other than by the Tandridge District Council for the purposes for which it was originally commissioned and prepared. JBA Consulting has no liability regarding the use of this report except to Tandridge District Council. Acknowledgements JBA Consulting would like to thank Mark Bristow of Tandridge District Council, Robert Kenway and Owen Davies from the Environment Agency, SES Water, Southern Water and Thames Water for their assistance in preparing this report. Copyright © Jeremy Benn Associates Limited 2018. Carbon footprint A printed copy of the main text in this document will result in a carbon footprint of 214g if 100% post-consumer recycled paper is used and 237g if primary-source paper is used. These figures assume the report is printed in black and white on A4 paper and in duplex. JBA is aiming to reduce its per capita carbon emissions. Water Cycle Study (Stage 3) 2018 i Executive summary In February 2018, JBA Consulting was commissioned by Tandridge Council to undertake a Water Cycle Study (WCS). This Phase 3 Detailed Study builds on the assessments completed in Phases 1 and 2 and provides evidence to support Tandridge’s Local Plan Process. This study assesses the potential issues relating to future development within Tandridge and the impacts on water supply, wastewater collection and waste water treatment. The Water Cycle Study is required to assess the constraints and requirements that will arise from potential growth on the water infrastructure. New homes require the provision of clean water, safe disposal of wastewater and protection from flooding. The allocation of large numbers of new homes in certain locations may result in the capacity of existing available infrastructure being exceeded, a situation that could potentially cause service failures to water and wastewater customers, adverse impacts to the environment, or high costs for the upgrade of water and wastewater assets being passed on to the bill payers. In addition to increased housing demand, future climate change presents further challenges to pressures on the existing water infrastructure network, including increased intensive rainfall events and a higher frequency of drought events. Sustainable planning for water must now take this into account. The water cycle can be seen in the figure below and shows how the natural and man-made processes and systems interact to collect, store or transport water in the environment. The Water Cycle Source: Environment Agency – Water Cycle Study Guidance This study will assist the council to select and develop sustainable development allocations where there is minimal impact on the environment, water quality, water resources, infrastructure, and flood risk. This has been achieved by identifying areas where there may be conflict between any proposed development, the requirements of the environment and by recommending potential solutions to these conflicts. The Water Cycle Study has been carried out in co-operation with the Environment Agency, SES Water, Southern Water and Thames Water, as well as the neighbouring Local Planning Authorities (LPAs). Water Cycle Study (Stage 3) 2018 ii Potential development sites were provided by Tandridge District Council and wastewater treatment works (WwTW) likely to serve growth in the area were identified using the Environment Agency Consents database. Each development site was then allocated to a WwTW in order to understand the additional wastewater flow resulting from the planned growth. Infrastructure required to address issues identified in the Phase 2 Outline Study was assessed to answer the following questions: What infrastructure is required When is it needed? Is the strategy sustainable? How is it going to be funded and implemented? For the purposes of this study, development sites were grouped into wastewater catchment to allow assessments to be made at the site, catchment, and water resource zone scale. Indicative timescales for delivery of infrastructure required to serve growth in the district were presented and identified careful phasing of development sites may be required in order to ensure the right infrastructure is in place prior to sites being occupied, and to prevent deterioration in the water environment. Water Cycle Study (Stage 3) 2018 iii Contents 1. Introduction ............................................................................................... 8 1.1 Terms of Reference ......................................................................................................... 8 1.2 The Water Cycle ............................................................................................................. 8 1.3 Impacts of Development on the Water Cycle ...................................................................... 9 1.4 Objectives ...................................................................................................................... 9 1.5 Study Area ..................................................................................................................... 9 1.6 Record of Engagement....................................................................................................10 1.6.1 Introduction................................................................................................................................... 10 1.6.2 Scoping Study Engagement ............................................................................................................. 10 2. Future Growth in Tandridge ........................................................................ 11 2.1 Study area ....................................................................................................................11 2.2 Components of the growth forecast ..................................................................................13 2.3 Changes to growth forecast used in Phase 2 ......................................................................13 3. Capacity for growth in Tandridge ................................................................. 14 3.1 Introduction ..................................................................................................................14 3.2 Beddington catchment ....................................................................................................15 3.3 Burstow catchment ........................................................................................................19 3.4 Felbridge catchment .......................................................................................................22 3.5 Godstone catchment ......................................................................................................25 3.6 Lingfield catchment ........................................................................................................28 3.7 Oxted catchment ...........................................................................................................31 3.8 Reigate catchment .........................................................................................................34 4. Water Quality ........................................................................................... 37 4.1 Groundwater Quality ......................................................................................................37 4.1.1 Groundwater Protection .................................................................................................................. 37 4.2 WINEP Schemes ............................................................................................................40 4.2.1 Introduction................................................................................................................................... 40 4.2.2 Methodology .................................................................................................................................. 42 4.2.3 Results .......................................................................................................................................... 43 4.2.4 Conclusion ..................................................................................................................................... 44 5. Sources of funding .................................................................................... 45 5.1 Water supply and wastewater infrastructure ......................................................................45