DOCSLIB.ORG

DAP REVIEW (OFWAT Report)

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
DAP REVIEW (OFWAT Report) WaPUG Spring Conference 2012 Paper 1 Elisa Zamora Atkins Principal Consultant [email protected] DAP REVIEW (OFWAT Report) Introduction and background Sewerage planning is largely targeted at resolving and avoiding the adverse consequences of failure of the sewerage system in terms of flooding and pollution. Water and sewerage companies have adapted their approaches to these tasks over time. Variation in responses by companies as part of historic regulatory reporting led Ofwat to seek a more detailed understanding of company practices. Additionally, Ofwat wanted to understand how sewerage planning tools are used by companies, both in planning for the long term and on a business as usual basis. We carried out a high-level review of company practices in August 2011 based on structured interviews with all ten water and sewerage companies in England and Wales. We would like to thank Anglian Water, Dŵr Cymru Welsh Water, Northumbrian Water, Severn Trent Water, Southern Water, South West Water, Thames Water, United Utilities, Wessex Water and Yorkshire Water for their participation. We would also like to thank the Water Services Regulation Authority (Ofwat), the Department for Environment, Food and Rural Affairs (Defra) and the Environment Agency (EA) for contributing their views on current and future practices to support a sustainable drainage industry. Objectives Our objectives included: understanding processes, systems and tools companies have to support robust long term sustainable planning. clearly articulating the approaches and common themes across the industry to a wide range of stakeholders, highlighting good practice. indentifying improvements that could be made to incentivise: Proactive management of the sewerage system to prevent failure occurring Robust decision making to ensure that developments are located in the most sustainable way The greater understanding of drainage systems required if companies are to implement demand reduction rather than increasing capacity. Key observations Companies have differed in their interpretation of the term DAP for historic reporting purposes The majority of companies are no longer commissioning new DAPs for sewerage planning Different systems are being used to deliver the outputs previously delivered by a DAP, although hydraulic analyses of the network are undertaken to understand pollution and flooding issues by all companies All companies are moving towards parallel procedures covering structural, operational and hydraulic analysis of the network with variable degrees of integration When updating hydraulic models, drainage area or sewerage management plans, the most common triggers are o In response to emerging issues o On a risk-based approach o On a rolling programme basis Hydraulic models are maintained rather than rebuilt where appropriate The information obtained through sewerage planning is used by all companies to support their investment planning process The degree to which sewerage planning tools are used to support the development of long term sustainable solutions is variable Generally companies use separate planning tools for sewage treatment and sewer networks, although some companies are evaluating investment needs in an integrated approach. Understanding what processes, systems and tools companies have to support robust long term sustainable planning Companies use drainage area plans (DAPs), drainage area studies (DAS), sewerage management plans (SMPs) or other approaches developed for sewerage planning. When historically reporting “DAP updates”, companies were generally referring to updating of the hydraulic model associated with the DAP, SMP or other. AMP5 approaches to sewerage planning can be grouped into three groups: Group 1 Group 2 Group 3 Hydraulic, structural and Hydraulic issues considered in Hydraulic, structural and operational issues considered specific catchments; structural operational issues considered in on a company wide basis and operational issues defined catchments (traditional considered on a company wide DAP approach) basis Companies have a range of tools for carrying out hydraulic assessments of the network ranging from headroom calculators to verified hydraulic models. Where hydraulic modelling is used, companies undertake this in accordance with the WaPUG Code of Practice (2002), which is the industry standard reference. Coverage of hydraulic systems ranges up to 100%. Companies with less than 100% coverage focus on having cover in larger catchments. Companies with 100% coverage use a risk based approach where more detailed information, such as verified Type II or III models, is available for areas considered high risk and lower risk areas are covered by a more simplified model or headroom calculator. Systems for managing structural and operational failures tend to be regional rather than catchment based. These tend to make use of business as usual data such as CCTV surveys and registers of flooding and pollution incidents. The outputs of the process are used internally for capital and operational maintenance planning and for defining wastewater supply-demand investment. In some cases systems based on current or live data are used for planning operational maintenance activities such as jetting. Company systems for capital maintenance planning, such as sewer rehabilitation, may be integrated with the sewerage planning process or informed by it. Longer term investment planning for wastewater infrastructure supply-demand is generally based on a 25 year horizon. The main issue faced by companies is the uncertainty of planned development. External uses include informing the development process and providing information for surface water management plans (SWMPs). All companies use information on hydraulic capacity to support their planning liaison processes, but the extent to which engagement in planning is a pro-active process varies across companies. Company engagement in the development of SWMPs is predominantly through the provision of hydraulic models. The majority of companies consider the sewerage network and sewage treatment separately although common data on population and flow is generally used for both. Good practice examples Planning on a regional basis: Historically, DAPs considered service failures within a given catchment only. This meant that, where DAP coverage was low, the company would not have full visibility of all the issues. A regional approach enables all issues to be appropriately prioritised, regardless of whether there is a DAP for the area. Use of risk-based approaches to assess hydraulic capacity: Analysis using less complex tools can help to inform where a more detailed model is required and allows companies to effectively target investment in hydraulic tools on a risk basis. Confidence scoring of hydraulic models: A confidence scoring system allows the user to determine whether the model is suitable for the purpose for which it is intended, thereby avoiding costs associated with unnecessary model rebuilds. It also allows targeted model maintenance to address the issue that will make the model fit for purpose. Use live and/or real-time data in the process: This results in live plans which can be used in operational management of the network as well as investment planning, enabling technology such as real-time network control. Also, this means decisions are being made using the most up to date information and remove the need for periodic updates of models or plans. Pro-active engagement in the planning process: This enables companies to make an informed assessment about the scale of future development for their own planning purposes, develop appropriate tools where needed, influence the location of planned development and facilitate the planning process. It supports a risk based assessment of planning. Integrated asset planning: In their move away from DAPs, some companies have developed a very integrated system based approach to identify and prioritise the investment to deliver the business outcomes needed e.g. serviceability. Integrating the business as usual systems with those used for longer term planning is both efficient and effective. Articulation of the approaches and common themes across the industry to a wide range of stakeholders We identified a number of common themes and differences in the approaches to sewerage planning now being taken by companies: Common themes Key differences planning on a regional rather than a catchment basis How the impacts of urban creep and climate change are considered in planning taking a risk based approach to the level of detail in a given integration of non-infrastructure and infrastructure area planning the use of quality assurance procedures for the management The degree to which systems and data can be of hydraulic models considered live the way in which updates to hydraulic models are triggered the use of sustainable techniques and planning for sustainable solutions the use of WaPUG Type II and Type III models how pro-active companies are in planning headroom calculators and /or hydraulic models being used to the scale of charges levied on developers. assess the impacts of development the use of business as usual data and planning on a 25 year horizon Company practices can be summarised in a stylised process: Recommendations for proactive management of the sewerage system to prevent failure occurring Use live / real time data for flow monitoring and operational control to enable headroom to be fully utilised Consistently accounting for
Load more

Recommended publications
  • Climate Change Adaptation Report Consultation
    Climate Change Adaptation Report Consultation 1 Online questionnaire responses Please note: all consultation responses have been published verbatim without edits. Do you support Are there any further Do you agree our adaptation opportunities to Comments in response to further Type of with our Comments in response to Anglian Water’s Comments in response to Anglian Water’s Anglian Water’s (brief) response to Organisation strategy and collaborate and opportunities to collaborate and solve Organisation assessment of assessment of climate risks adaptation strategy and proposed actions consultation comments the actions we solve problems in problems in partnership climate risks? propose to take? partnership? University Cardiff University/ Y None Y An important element of future plans is Y Following on from our previous comment. We agree. For the past three years we have Centre for demand reduction. We strongly support this There is an opportunity to research how been trialling a second generation of smart Climate Change strategy. However, it also appears that a smart meters may help (or not) reduce meters, in two areas: Newmarket (Suffolk) and Social substantial section of demand reduction will water demand. It may also be interesting and part of Norwich. The Newmarket trial has Transformations be driven by smart metering. It is not clear to examine how different elements of the been combined with a whole-town focus on how successful this will be. Studies on energy demand reduction strategies can work in water efficiency and wider communications smart meters has shown that it may lead to parallel and therefore lead to greater savings about water.
    [Show full text]
  • Gate One Submission for Thames Water to Southern Water Transfer Date: 05 July 2021
    Strategic regional water resource solutions: Preliminary feasibility assessment Gate one submission for Thames Water to Southern Water Transfer Date: 05 July 2021 i Glossary Acronym Terms to use / Definition AA Appropriate Assessment - under the Habitats Regulations ACWG All Company Working Group AIC Average Incremental Cost AMP Asset Management Plan AONB Area of Outstanding Natural Beauty BBOWT Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust BNG Biodiversity net gain BNL Biodiversity net loss CAP Competitively Appointed Provider CCG Customer Challenge Group – a regional CCG has been established by WRSE CCW Consumer Council for Water CEB Chemically Enhanced Backwash CEC Contaminants of Emerging Concern CEMP Construction and Environmental Management Plan CO2 Carbon Dioxide CPO Compulsory Purchase Order DAF Dissolved Air Floatation DCO Development Consent Order – planning under the Planning Act 2008 Defra Department for Environment, Food and Rural Affairs DI Ductile Iron DO Deployable Output DPC Direct Procurement for Customers DWI Drinking Water Inspectorate DYAA Dry Year Annual Average EA Environment Agency EES Thames Water’s Engineering Estimating System EIA Environmental Impact Assessment ENG Environmental Net Gain ERD Energy Recovery Devices FD Ofwat Final Determination FEPS Final Effluent Pumping Station GAC Granular Activated Carbon HE Historic England HIOWWT Hampshire and Isle of Wight Wildlife Trust HRA Habitat Regulations Assessment ICA Instrumentation Control and Automation INNS Invasive Non-Native Species IP Infrastructure
    [Show full text]
  • Copyrighted Material
    5 1 Water, Policy and Procedure There is a certain relief in change, even though it be from bad to worse; as I have found in traveling in a stagecoach, that it often a comfort to shift one’s position and be bruised in a new place. Tales of a Traveller, Washington Irving (1824) 1.1 ­Pressing Needs for Conservation and Protection? Among the nations, the three constituent countries of Great Britain (England, Wales and Scotland) were early to industrialise and have been that way for around two and a half centuries. While this observation sets the scene for an account of the water resources of Britain, the last 30 or more years have seen dramatic changes away from the heavy indus­ trial sector. Yet problems persist, particularly where ‘technical fixes’ have not ­provided solutions. Once it was assumed that regulatory measures, and especially ‘end of pipe’ pollution problems are solved (in theory) through consenting and licencing, yet diffuse pollution of waters persists from a range of contaminants and from a range of industrial and other activities. These result largely from the ways by which we conduct our econ­ omy and new solutions are sought. Not only is Britain definitively to manage its water resources on a catchment (or river basin) basis, but new political imperatives are ­emerging that require water management in part to become an extension of ‘civil ­society;’ this eclipses older ideas about ‘technocratic management’. This chapter outlines the present issues for sustainability and sustainable develop­ ment in water resources, and it also scopes out the challenges.
    [Show full text]
  • Potable Freshwater Pre-Planning Enquiry
    Potable freshwater pre-planning enquiry A pre-planning enquiry can assist developers in identifying possible constraints that may be associated with servicing a development site and the potential costs and timescales involved in servicing a site prior to land acquisition or the submission of a planning application. Please complete this form and save a copy and email it to [email protected] or alternatively post it to: Developer Services, Southern House, Yeoman Road, Worthing, West Sussex BN13 3NX All fields are required unless otherwise stated. Please note incomplete information may cause delays to your application. When answering the yes/no questions please tick in the appropriate box. Please keep a copy of the completed application for your records. If you need any help completing the form please call us on 0330 303 0119 and we’ll be happy to help. We aim to respond to enquiries within five calendar days from receipt of your completed enquiry form. Section 1: About you Are you? (please tick) Developer Consultant Landowner Other (please state) Name: Address: Company name (if applicable): Phone: Email: Postcode: Section 2: Development details Please see our portal for further details: developerservices.southernwater.co.uk. For developments of less than 500 units a Level 1 preliminary freshwater capacity can be undertaken. This is a simple check that will identify whether the required capacity is available adjacent to or close to the proposed development. Should capacity not be available, you will be provided with an indication of the nearest point at which capacity is available and a Level 2 Indicative Hydraulic Assessment can be considered.
    [Show full text]
  • Service Connections User Guide
    Service connections user guide March 2021 Developer Services Service connection user guide About South Staffs and Cambridge Water South Staffordshire Water PLC (‘South Staffs Water’) is part of the South Staffordshire Plc group of companies, a privately-owned integrated services group concentrating on regulated water supply and complementary specialist service businesses. We operate across two regions under a single water supply licence, providing clean water services to more than 1.7 million people and around 43,000 businesses in Staffordshire, parts of the West Midlands, and in and around Cambridge. Our South Staffs region extends from Ashbourne in the north to Halesowen in the south, and from Burton-upon-Trent in the east to Kinver in the west. Our Cambridge region stretches from Ramsey in the north to beyond Melbourn in the south, and from Gamlingay in the west to the east of Cambridge city. Cambridge region South Staffs region 1 Developer Services Service connection user guide Contents About South Staffs and Cambridge Water ................................................................................ 1 Contents .................................................................................................................................... 2 1. Introduction ........................................................................................................................... 3 2. Who can complete this work?............................................................................................... 5 3. What is the process
    [Show full text]
  • Accommodating Growth and New Development: Response to IAP
    Appendix 10 – Accommodating growth and new development: Response to IAP Wessex Water March 2019 Appendix 10 – Accommodating growth and new development: Wessex Water Response to IAP Summary This appendix provides additional evidence in relation to Ofwat’s cost assessment for wastewater network+ growth for the following drivers: • Growth at sewage treatment works • New development • First time sewerage. The table below summarises the additional evidence provided, our response to the cost assessment in the initial assessment of plans (IAP) received in January 2019, and the actions that we suggest Ofwat take prior to the draft determination. Ofwat model / Driver Value Our response Suggested actions challenged for Ofwat £m Table WWn8 Line 7 (also in Table Additional evidence Review the drivers for WWS2 Line 26) regarding the validity of our the implicit allowance • Cost adjustment claim for cost adjustment claim and growth model and STW capacity why this has not been reassess the cost 19.2 programme. Capex accounted for within the adjustment claim for baseline model for growth, STW growth based on i.e. the model does not the further evidence. reflect our unique position. Table WWS2 Line 73 Refer to our main document, Our Response to • Growth at sewage Ofwat’s Initial Assessment of Plans – section 3.3.3 treatment works 1.4 (excluding sludge treatment). Opex Table WWS2 Lines 25 We have provided Use our bottom up • New development and additional evidence of our approach and allow growth (Wastewater 12.8 bottom up approach to capex costs submitted network supply demand assessing the need for balance). Capex investment. Table WWS2 Line 72 Refer to our main document, Our Response to • New development and 3.6 Ofwat’s Initial Assessment of Plans – section 3.3.3 growth.
    [Show full text]
  • Completed Acquisition by South Staffordshire Plc of Cambridge Water Plc
    Completed acquisition by South Staffordshire plc of Cambridge Water plc ME/5254/11 The OFT's decision on reference under section 32(b) given on 5 January 2012. Full text of decision published 9 January 2012. Please note that the square brackets indicate figures or text which have been deleted or replaced in ranges at the request of the parties or third parties for reasons of commercial confidentiality. PARTIES 1. South Staffordshire Plc ('South Staffordshire') is a public company limited by shares and incorporated in the United Kingdom. South Staffordshire owns South Staffordshire Water Plc ('South Staffordshire Water') and is the holding company for a number of non-regulated service businesses that operate predominantly in the UK water sector. South Staffordshire is an indirect wholly-owned subsidiary of investment funds management by Alinda Capital Partners LLC. 2. South Staffordshire Water is a water company whose assets include a network infrastructure (mains infrastructure, water treatment works and pumping stations) for the supply of water in the South Staffordshire area and does not have regulated sewerage businesses. South Staffordshire also has a number of subsidiaries providing non- regulated business activities. The turnover for the year ended 31 March 2011 for both South Staffordshire and South Staffordshire Water was £159.5 million and £87.8 million respectively. 1 3. Cambridge Water plc ('Cambridge Water') was a wholly-owned subsidiary of HSBC Bank Plc ('HSBC')1 (until its acquisition by South Staffordshire Plc on 3 October 2011). 4. Cambridge Water is also a water company that owns a network infrastructure (mains infrastructure, water treatment works and pumping stations) for the supply of water in the Cambridge area and does not have regulated sewerage businesses.
    [Show full text]
  • Our Response to Ofwat's Initial Assessment of Plans
    Our response to Ofwat’s initial assessment of plans April 2019 wessexwater.co.uk Our Response to Ofwat’s Initial Assessment of Plans Wessex Water Executive summary This document sets out the updates we have made to our Business Plan for 2020-2025 following: • Ofwat’s initial assessment of plans which it published in January 2019 • our continued engagement with our customers • engagement with the Wessex Water Partnership (who act as our regulatory Customer Challenge Group) • updated information from environmental regulators about the required outcomes. We understand the need to continue to show great value in the round as well as excellent services to our customers. Our board remains committed to: • putting customers and communities at the heart of what we do • embracing change and innovation through our open systems model • environmental leadership • investing in our people and skills • sharing our success with the wider community. Updates to our plan mean that in 2020 average bills to customers will now reduce by 10% in real terms. By 2025 bills will remain 6% less than today in real terms despite having completed our largest ever set of environmental and service improvements. As a result our customers and the environment will continue to get the best service levels of any water company in the UK. Since September 2018 we have reduced the forecast expenditure in our plan by £43m. The reductions are to take account of new information about our obligations including, at Ofwat’s suggestion, where the performance target level that the industry is required to meet is less ambitious than we had originally proposed.
    [Show full text]
  • Proposals for Selsey
    Our Bathing Water Enhancement Programme - proposals for Selsey Working together to protect and enhance bathing water across our region between now and summer 2019 Protecting and enhancing our bathing waters Our region’s bathing waters are precious and among the cleanest in the UK, and you’ve quite rightly asked us to continue to protect and enhance them. So, we’re carrying out a multi-million pound Bathing Water Enhancement Programme, the first of its kind in the UK, to do just that. We’ve set aside £31.5 million of funding for this innovative programme, and are working together with local councils, the Environment Agency and other stakeholders to deliver it. Between now and the 2019 bathing season, we’ll work together to investigate 21 of our region’s beautiful bathing waters, and to make sure that seven of them reach the ‘excellent’ quality standard. Although our programme’s investment comes to an end in 2019, we’re confident the enhancements that are delivered will help to maintain excellent water quality at these sites for many years to come. Dartford Gravesend Our bathing waters Herne Bay Isle of Chatham Sheppey Ramsgate Gillingham Canterbury Faversham Sevenoaks Maidstone Deal Basingstoke SUTTON & Andover EAST SURREY SOUTH EAST Tonbridge WATER THAMES WATER KENT Dover WATER Ashford SOUTH EAST Tunbridge Wells Folkestone WESSEX WATER Crawley WATER Haslemere Weir Wood Bewl Water Winchester AFFINITY Salisbury Horsham Haywards EAST SUSSEX New WATER Otterbourne Heath Romney Petersfield Darwell HAMPSHIRE WEST SUSSEX Burgess SOUTH EAST Lydd
    [Show full text]
  • All Company Working Group Joint Document
    Representations: Strategic regional water resource solutions joint statement Document Reference: J007a This document is the joint representation with the other companies with strategic water resources schemes: Affinity Water, Anglian Water, Severn Trent Water, Southern Water, South West, Thames Water, Wessex and Water Resources South East. In this document general matters, which reflects the agreed position of all the companies United Utilities Water Limited Strategic regional water resource solutions Affinity Water, Anglian Water, Severn Trent Water, Southern Water, South West, Thames Water, United Utilities, Wessex Water 30 August 2019 Joint Company Statement Following the Draft Determination (DD) the working group has met several times to continue to work collaboratively to optimise the processes for developing the next set of strategic water resource solutions. The DD has added some additional options into the mix of schemes as well as increasing the number of companies working across the schemes from six to eight. These additional companies and schemes are welcomed as they will help provide additional choices when deriving the best value plans for customers, stakeholders and the environment. Our engagement with the regulators during the development of the plan have continued to help and shape this response. The recent meetings with RAPID, EA and Ofwat (in July and August) have been very encouraging and we look forward to working collaboratively to align the gated processes, national framework timetables and statutory planning processes. We want to ensure that the timetables and processes are efficient and co-ordinated, and we believe we can achieve this through a few simple re-alignments of some of the gates during the process.
    [Show full text]
  • Modification of the Conditions of Appointment of Southern Water Services Limited
    WATER SERVICES REGULATION AUTHORITY WATER INDUSTRY ACT 1991, SECTION 13(1) Modification of the Conditions of Appointment of Southern Water Services Limited Made on 22 March 2021 Coming into effect on 23 March 2021 The Water Services Regulation Authority, in exercise of the power conferred on it by section 13(1) of the Water Industry Act 1991 (the "Act"), after giving notice as required by section 13(2) of the Act, hereby makes the modifications described in the Schedule attached hereto to the Conditions of the Appointments of Southern Water Services Limited (the "Appointee") as a water and sewerage undertaker under Chapter I of Part II of the Act, the Appointee having consented to these modifications. Signed for and on behalf of the Water Services Regulation Authority Keith Mason Senior Director Schedule 1. The following new definitions will be inserted into paragraph 3 of Condition A at the appropriate alphabetical place: “Capacity Charge” means the charge of that name under the Havant Thicket Agreement; “Havant Thicket Activities” has the meaning given to it in paragraph 2 of Condition B of the Instrument of Appointment of Portsmouth Water Limited; “Havant Thicket Agreement” means the agreement (including for the bulk supply of water) between the Appointee and Portsmouth Water Limited in respect of the Havant Thicket Activities; 2. The following new Condition T will be inserted after Condition S: “Condition T: Havant Thicket Introduction This Condition requires the Appointee to comply in all material respects with the terms of the Havant Thicket Agreement entered into between the Appointee and Portsmouth Water Limited.
    [Show full text]
  • Your Charges Explained 2019-20 Contents Introduction
    Your charges explained 2019-20 Contents Introduction Each year we set our charges according to price limits that are determined by Introduction 1 Ofwat every five years. Prices were set for the period between 2015-2020 following reviews that started in 2014. Charges 2019-20 2 This leaflet explains more about Ofwat’s price limits, how you are charged and How you are charged 3 where the money goes. Metered customers 4 Charges for Bristol Water and Wessex Water are collected by Bristol Wessex Billing Services Limited (BWBSL). Unmetered customers 6 Charges applicable from 1 April are published on company websites early in Where your money goes 8 February. Visit bristolwater.co.uk or wessexwater.co.uk or call 0345 600 3 600 (Monday to Friday, 8am to 8pm; Saturday, 8am to 2pm). Common questions 10 Further information about charges is also available from our regulator Do you qualify for the surface www.ofwat.gov.uk water rebate 12 1 Charges 2019-20 How you are charged Our charges from 1 April 2019 to 31 March 2020 are shown below. Charges for water and sewerage The difference between Metered charges Bristol Water Wessex Water services are either based on how metered and unmetered Water supply much water you use (metered charge) charges or the rateable value (RV) of your Standing charge per annum £41.00 - property (unmetered charge). We make sure that the difference Since 1991, meters have been between metered and unmetered bills Charge per cubic metre £1.3328 - installed in all newly built properties, reflects the difference in the cost of and Bristol Water’s aim is that all providing these services.
    [Show full text]