Final Water Resources Management Plan
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Cambridge Water Company Final Water Resources Management Plan Final Water Resources Management Plan January 2010 1 Cambridge Water Company Final Water Resources Management Plan Contents Page Executive Summary 3 1.0 Overview 1. 1 Introduction 5 1. 2 Consultation 5 1. 3 Summary of Plan 6 1. 4 Cambridge Water Cycle Study 7 1. 5 Directions 7 2.0 Water Resources Plan 2. 1 Plan Content and Development 9 2. 2 Water Supply 12 2. 3 Water Demand 15 2. 4 Climate Change 25 2. 5 Greenhouse Gas Emissions 27 2. 6 Target Headroom 27 2. 7 Baseline Supply-Demand Balance 28 2. 8 Option Appraisal 28 2. 9 Final Water Resources Strategy 29 3.0 Tables 31 4.0 Appendices 1 - Consultation 32 2 - Strategic Environmental Assessment 36 3 - Economic Level of Leakage Assessment * 48 4 - Target Headroom Calculation * 49 5 - Effects of Climate Change on Supply 50 6 – Outage Assessment * 54 7 – 25 Year Appraisal of Metering Policies 55 * available on request 2 Cambridge Water Company Final Water Resources Management Plan Executive Summary Cambridge Water’s water resources management plan sets out how the Company will manage its resources to meet the needs of existing and future customers, and those of the environment, over the next 25 years. The Company’s supply-demand balance (the amount of water available for use, compared with the quantity actually used) could be influenced by a range of factors: this plan describes those factors, and assesses their likelihood and impact. Using this assessment the Company’s supply-demand surplus (headroom) has been calculated over the planning period. An additional buffer (target headroom) has been included to cater for uncertainties. The Board of Cambridge Water Company reviewed and endorsed the draft water resources management plan and its underlying policies at a Board Meeting held on 4th March 2008. Following publication, and a period of consultation, the draft plan was updated to take account of representations received during the consultation period and changes in the economic climate. Further information was requested by, and provided to, the Secretary of State, who subsequently agreed that this final plan should be published. Baseline Water Resources Situation Significant growth in housing numbers is planned for the Cambridge sub-region over the next 15 years. Cambridge Water has seen a rise in new housing connections over the past few years, and expects this trend to continue throughout the planning period. The Company has taken a view on the likely annual increase in housing numbers, based on the expectations set out in the East of England Plan, experience of the planning process, and historic build rates. Per property consumption for the new homes is forecast to be lower than traditionally assumed, as the principles set out in the Code for Sustainable Homes are incorporated into planning and building policy. Modest growth in per capita consumption at existing properties is forecast: at this stage, the Company sees no significant savings arising from the retro-fitting of water-efficient devices on a large scale. A percentage of existing unmeasured household customers is expected to opt to pay for their water on a measured basis, at a similar rate to that witnessed in recent years. In line with published guidance, overall demand for water is expected to increase by up to 2% over the planning period as a result of climate change alone. The Company expects to maintain total leakage at 14 megalitres per day (Ml/d), effectively reducing per property leakage by 35% by 2035, from 110 litres/property/day to 73 l/prop/d. On the supply side, the planned refurbishment of one of the Company’s sources in 2009/10 will allow its full licensed quantity to be abstracted, providing a small increase in deployable output (DO) *. This increase is likely to be offset by a small loss of DO arising from a sustainability reduction applied by the Environment Agency. The reduction is the probable outcome of a series of investigations at a number of sources whose abstractions had been thought by the Agency, and Natural England, to have a possible detrimental effect on nearby environmental sites. However, the value of the likely reduction is not yet ascertained so, in accordance with the latest Agency guidance, no reduction in deployable output has been assumed at this stage. * deployable output is the amount that can be pumped from the Company’s sources, constrained by licence, geophysical features, or plant limitations. 3 Cambridge Water Company Final Water Resources Management Plan Towards the end of the planning period, in order to preserve headroom, the Company will introduce measures to improve the security of supply at strategic single-borehole sites, as a means of reducing outage. These measures will not have a significant effect on the environment. Recent studies show that climate change may also result in a small loss of deployable output, spread over a percentage of the Company’s sources. More work will be carried out in this area when the Environment Agency’s regional groundwater model is fully developed. Under the baseline scenario headroom is expected to be maintained throughout the planning period. Figure 1 illustrates the projected supply-demand balance, under the baseline scenario, over the period. Final Planning Solution Cambridge Water’s supply area has been designated by the Environment Agency as an “area of serious water stress”, which gives the Company powers to increase meter penetration through a compulsory metering programme. As a result of previous investment in metering initiatives Cambridge Water already has one of the highest levels of household meter penetration among water companies. This plan expects meter penetration to increase to 88% of all billed households by 2035. Over 70% of the water currently supplied by Cambridge Water is on a measured basis, and the benefits of this level of metering in curbing peak demand have been readily seen over recent years. There is no immediate threat to water resources in the Company’s area, and we do not propose to undertake an accelerated household metering programme during the planning period. Given the Company’s current healthy supply-demand balance, there is no justification or benefit to be gained in the short-term from making significant investment in capital schemes designed to alter that balance. Taking the above factors into account, the Company has not found it necessary to include a final planning solution in its final plan. 4 120 115 110 deployable output forecast TWAFU - target headroom 105 dry year demand forecast (baseline) 100 Ml/d 95 Fig.1 - Baseline Forecast 90 85 80 75 70 2007-08 total water available for use (TWAFU) 2008-09 dry year forecast (baseline) incl. climate change outage 2009-10 normal year demand forecast (baseline) target headroom 2010-11 2011-12 supply demand balance 2012-13 2013-14 2014-15 2015-16 2016-17 2017-18 2018-19 2019-20 2020-21 2021-22 2022-23 2023-24 2024-25 2025-26 2026-27 2027-28 2028-29 2029-30 2030-31 2031-32 2032-33 2033-34 2034-35 Cambridge Water Company Final Water Resources Management Plan 1.0 Overview 1.1 Introduction This draft water resources management plan (WRMP) shows how Cambridge Water Company intends to maintain the balance between supply and demand over the next 25 years. The plan is complemented by the Company’s drought plan, published in early 2008, which sets out the short-term operational steps Cambridge Water will take if a drought occurs. The Company published its first water resources plan in March 1999. This was later superseded by a second version, published in March 2004, after consultation with the Environment Agency. The Water Act 2003, by amending the Water Industry Act 1991, introduced a statutory duty for water companies to prepare and maintain water resources plans. The Water Resources Management Plan Regulations 2007 prescribe how plans are to be prepared and published, and the latest guidance issued by the Environment Agency (EA) in April 2007 covers this process in detail. This plan has been prepared in line with Directions* from the Secretary of State, and the latest EA guidance. Responses received from consultees at the pre-draft stage have also been considered in the compilation of this document. The Board of Cambridge Water Company reviewed and endorsed the draft water resources management plan and its underlying policies at a Board Meeting held on 4th March 2008. Following publication, and a period of consultation, this draft plan has been updated to take account of representations received. The updated draft plan, together with the Company’s statement of response to the representations received, were considered by the Secretary of State, who requested further information to enable a decision to be made regarding publication of Cambridge Water’s final plan: this was provided in October 2009. Having considered the further information provided, the Secretary of State agreed, in December 2009, that the final plan should be published. * a summary of the Directions made by the Secretary of State, and assurance that this plan complies with those Directions, is set out in Section 1.5 below. 1.2 Consultation The statutory process for the preparation of water resources management plans sets out defined stages for consultation. The three principal consultation stages are: Pre-draft consultation with statutory consultees and licensed water suppliers (see Note below) Consultation with the Environment Agency’s regional planners, and with the Company’s Water Services Regulation Authority (Ofwat) Reporter during the preparation of this draft plan Consultation with specified organisations, with the Company’s customers, and with anyone else who is likely to be affected, following publication of the draft plan.