Draft Water Resources Management Plan 2019
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Draft PR19 Water Resources Management Plan Northumbrian Water Draft Water Resources Management Plan 2019 March 2018 0 DOCUMENT CONTROL SHEET Report Title Final Water Resources Management Plan Release Date 5th March 2018 Report Status Draft Authors John Gray, Ian Walker, Liz Wright, Katherine Fuller, Alan Gosling, Andrew Austin, Dennis Dellow, Simon Welsh Previous Northumbrian Water - Water Resources Management Plan (2009) Issue Northumbrian Water - Water Resources Management Plan (2014) Distribution Internal : Applicable Management & Affected Depts List External : OFWAT, Environment Agency, Secretary of State (c/o DEFRA), Regional Development Agencies in the area covered by the Plan, Elected Regional Assembly in the area of the Plan, Local authorities in the area of the Plan, Natural England, The Historic Buildings and Monuments Commission for England, Navigation authorities in the area of the Plan, Consumer Council for Water. Version Reviewed by Approved by Date Martin Lunn Draft NWG Board 30 November 2017 John Devall Exclusions on the Grounds of National Security Northumbrian Water Limited has not excluded any information from this plan on the grounds that the information would be contrary to the interests of national security. Under Section 37B(10)(b) of the Water Industry Act 1991, as amended by the Water Act 2003 (“the Act”), the Secretary of State can direct the company to exclude any information from the published Plan on the grounds that it appears to him that its publication would be contrary to the interests of national security. Disclaimer : This report is intended as confidential to the individuals and or companies listed on the distribution list. Northumbrian Water accept no responsibility of any nature to any third party to whom this report or any part thereof is made known. Northumbrian Water is a trading division of Northumbrian Water Limited which is a group company of Northumbrian Water Group Registered in England & Wales No. 2366703 Registered Office: Northumbria House, Abbey Road Pity Me, Durham DH1 5FJ DRAFT WATER RESOURCES MANAGEMENT PLAN 2019 Page 1 Non-Technical Summary Introduction Water Resources Management Plan Purpose This document is Northumbrian Water’s (NW) draft Water Resources Management Plan (WRMP). It demonstrates that NW has an efficient, sustainable secure supply of water over the Company’s chosen planning period. For this WRMP, the Company has prepared water demand and supply forecasts for a 40 year planning period from 1st April 2020 to 31st March 2060. The WRMP covers the entire NW customer supply area (see Figure 1). For the purposes of the Company’s demand forecasts and supply demand balance calculations, the supply area has been split into the following Water Resource Zones (WRZ): . Kielder WRZ; and . Berwick & Fowberry WRZ The WRMP has been prepared following the Water Resources Management Plan (England) Direction 2017, Defra’s Guiding Principles for Water Resources Planning (May 2016) and the Environment Agency’s (the Agency) Water Resources Planning Guideline (WRPG) (April 2017). The Kielder WRZ benefits from Kielder Reservoir and the Kielder Transfer Scheme. Kielder Reservoir, located in Northumberland, is the largest artificial lake in the United Kingdom by capacity holding 200 billion litres (200,000Ml) of water. The reservoir supports flow in the North Tyne to support abstractions of water further downstream. It also supports the Kielder Transfer Scheme which enables water to be transferred to the Wear, Derwent and the Tees rivers. Kielder Reservoir and transfer scheme collectively make the Kielder WRZ one of, if not the most resilient WRZs in the country. The supply forecast Water Available for Use (WAFU) presented in this draft WRMP is based on updated reservoir control curves that NW has agreed with the Environment Agency and the existing raw water pumping station infrastructure. This WAFU provides the WRZ with a significant dry year supply surplus. However, it should be noted, that with different reservoir control curves to call on support from the Kielder Transfer Scheme, the Kielder WAFU and therefore supply surplus could be significantly higher than what NW currently report. PR19 Supply and Demand Forecasts In this draft WRMP, all components of the supply and demand forecasts have been reviewed using the appropriate methods recommended in the WRPG. The chosen planning scenario remains the Dry Year Annual Average (DYAA) as no WRZ demonstrates a critical period where peak demands are driving investment within the WRZ. DRAFT WATER RESOURCES MANAGEMENT PLAN 2019 Page 2 Water Supply Forecasts Future water supplies are forecast by calculating WAFU. WAFU is calculated by quantifying the Deployable Output (DO) of NW’s raw water sources and treatment works within each water resource zone. Outage (e.g. when a treatment works is out of supply due to planned maintenance), process losses (e.g. the water used to back wash treatment works filters) and sustainability reductions (e.g. where NW’s abstraction licence has been reduced to ensure they are sustainable) are then subtracted from DO to give WAFU. The Kielder WRZ WAFU has reduced by around 100Ml/d (at the end of the planning horizon) due to the updated methodology for calculating DO, the Berwick and Fowberry WAFU remains similar to PR14. Effect of Climate Change on Future Water Supplies Climate change was assessed using the i-Think models in our PR14 WRMP, as NW have now moved over to using Aquator to carry out NW’s water resource modelling an alternative method of assessing climate change for PR19 to that used for PR14 is required. As NW only has a limited number rainfall-runoff models for the Kielder System and the Kielder WRZ is at low vulnerability to climate change, the WRPG recommends that a tier 1 analysis is carried out, that being the use of Future Flows (FF) Hydrology change factors for the 2080s. The Kielder WRZ appears to be relatively sensitive to reductions in summer flows, this is due to the fact that under the baseline scenario, during the design drought year, some reservoir levels are already extremely low and the decrease in summer flows means that the reservoirs empty prior to the winter refill period. For the Berwick and Fowberry WRZ, no groundwater model is available to assess the impact of climate change. In order to provide climate change predictions on groundwater levels in this area, reductions in groundwater level in response to decreasing recharge as a result of climate change (based on UK Climate Projections 2009) are used along with Long Term Average recharge spreadsheet calculations. NW assessments conclude that after considering the effects of climate change, both WRZs remain in surplus across the whole planning horizon, with no water resource development being driven by climate change assumptions. Environmental Improvements Each time NW update the WRMP (every five years), NW agree with the regulators a list of schemes collectively known as the Water Industry National Environment Programme (WINEP). The WINEP is an integrated list of requirements for water resources, water quality and fisheries, biodiversity and geomorphology. It consists of investigations, options appraisals and actions to protect (prevent deterioration) and improve the water environment. Actions to protect or improve the environment include changes to NW’s abstraction licences, also known as sustainability changes, and non-licence change actions, such as river restoration. The WINEP does not just DRAFT WATER RESOURCES MANAGEMENT PLAN 2019 Page 3 consider the direct effect of abstraction. It also considers among other aspects catchment measures to improve the quality of water at abstraction intakes, Invasive non-native species risk, fish passage and discharges to the environment. The current Periodic Review (PR14) Asset Management Plan (AMP6) National Environment Programme (NEP) (2015 to 2020) includes the following: . Investigation into sustainable abstraction levels from the Fell Sandstone aquifer in the Berwick area; . Investigations and trials of variable compensation releases at five impounding reservoirs in the Kielder WRZ.; . Eight Eel Regulations Implementation Schemes, of which six were to improve intake screening and two to install or improve eel passes; . Two fish passage installations; . Water Quality / Drinking Water Protected Areas (DrWPA): o A programme of work under the DrWPA driver, implementing catchment schemes to protect raw water quality. NW has made excellent progress in delivering all of the above schemes. All of the improvements will have been delivered by 31st March 2020. NW has agreed a new WINEP with the regulators for AMP7 (2020 to 2025). The second iteration of the PR19 WINEP for AMP7, issued by the Agency in September 2017, contains the following schemes: Seven Sustainable Change investigations. One Eel Screen installation. Eight Investigations and Options Appraisals. Four Fish Passage Investigations. Five No deterioration schemes for catchment management work to protect water quality in some of the Company’s surface water catchments All of the above schemes will go forwards into NW’s PR19 Business Plan. Household Demand Forecast The base building block for demand forecasting is the base year population served and the projected growth in population annually over the WRMP. In line with the WRPG requirement, NW has used Local Plan housing growth evidence from all local authorities and has selected the Plan-based scenario. The population forecasts for PR19 using the plan-based scenario shows a growth in population over the planning horizon. This has resulted in a 23% increase in population over the 40 year planning horizon. The population is now forecast to be 3.15M by 2059/60. Overall occupancy in the demand forecast reduces from 2.33 to 2.27. The average annual number of new homes is forecast at 9,271 in AMP7 for NW. DRAFT WATER RESOURCES MANAGEMENT PLAN 2019 Page 4 The per capita consumption (PCC) in NW is forecast to reduce annually across the planning horizon as a result of the Company’s metering policy and water efficiency initiatives. Unmeasured PCC is forecast to reduce to 134.53 l/h/d by 2059/60 with measured properties reducing to 120.99 l/h/d.