The Role of Internal Drainage Boards in Managing Water Levels: Best Practice and Potential Future Roles
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www.defra.gov.uk The role of Internal Drainage Boards in managing water levels: Best practice and potential future roles R&D Technical Report WT1512/TR Produced: May 2013 Defra Water Availability and Quality R&D Programme The role of Internal Drainage Boards in managing water levels: Best practice and potential future roles R&D Technical Report WT1512/TR Produced: May 2013 Author(s): Risk & Policy Analysts (RPA) Statement of use This report is part of Defra’s Water Availability and Quality Research Programme. The project is designed to support Internal Drainage Boards (IDBs) in sharing best practice on increasing local resilience to climate change and learn from IDBs best practice as we look to develop more local and integrated approaches to water management. Dissemination status Internal: Released Internally External: Released to Public Domain Keywords: Water resources, climate change, water management, regulation Research contractor: Risk & Policy Analysts (RPA) Defra project officer: Zoe Fitzsimmons Publishing organisation Department for Environment, Food and Rural Affairs Water Availability Division, Nobel Houise, 17 Smith Square London SW1P 3JR © Crown copyright (Defra); 2013 Copyright in the typographical arrangement and design rests with the Crown. This publication (excluding the logo) may be reproduced free of charge in any format or medium provided that it is reproduced accurately and not used in a misleading context. The material must be acknowledged as Crown copyright with the title and source of the publication specified. The views expressed in this document are not necessarily those of Defra. Its officers, servants or agents accept no liability whatsoever for any loss or damage arising from the interpretation or use of the information, or reliance on views contained herein. The role of IDBs in managing water levels: best practice and potential future roles Final Report prepared for Defra 24 May 2013 The role of IDBs in managing water levels: Best practice and potential future roles May 2013 Final Report Quality Assurance (Bold) Project reference / title J795ext/abstraction Report status Final Report Teresa Fenn, Technical Director Elizabeth Daly, Consultant Yvette Le Crom, Researcher Jenny Miller, Researcher Author(s) Chloe Elding, Researcher Jamie Williams, Environment Systems Natalie Small, Environment Systems Gemma Bell, Environment Systems Approved for issue by Meg Postle, Director Date of issue 24 May 2013 Document Change Record Report Version Date Change details Incorporating comments on DFR, inclusion of maps, inclusion of FR 1 24 May 2013 additional information found to fill outstanding data gaps Disclaimer The views and propositions expressed herein are, unless otherwise stated, those of Risk & Policy Analysts and do not necessarily represent any official view of Defra or any other organisation mentioned in this report. Executive Summary Rationale for the study The challenges of climate change and increased demand for water from a growing population are predicted to extend the current abstraction management regime beyond what it was designed to cope with. In response to this, the 2011 Water White Paper: Water for Life, set out a vision, direction and process to reform the abstraction regime to make it more responsive to future uncertainty and enable water resources to be managed more effectively. Defra is working closely with stakeholders in developing reform proposals. This includes establishing the Abstraction Reform Advisory Group, which comprises representatives from major trade associations and environmental NGOs, to guide the development and assessment of the options. In parallel to developing reform proposals, Defra is increasing its efforts to reduce damaging abstraction now by making better use of existing tools. Internal Drainage Boards (IDBs) already have a broad role in managing water levels for farming, managing flood risk and improving biodiversity. There could also be opportunities for IDBs to play a role in water resource management more widely. There are strong synergies with a number of Defra policy areas, including the potential role of IDBs for water trading under a reformed water abstraction regime, and their role in local resilience to climate change. IDBs could offer the potential for local abstraction management, and also have potential to serve as brokers or facilitators of water trading. Aims and objectives The aims and objectives of this study are to: learn from IDB best practice on increasing and improving local resilience to climate change (looking at both too much and too little water) to help inform Defra during development of more local and integrated approaches to water management; and work with IDBs to identify and assess the potential of a range of enhanced roles for IDBs to help better manage extremes of water, and work to design future collaborations/groupings best placed to tackle water management at catchment level. Approach to the study The approaches used here include collection of primary and secondary data, through direct contact with individuals and internet searches. Data on the predicted effects of climate change and the activities of IDBs were available on the internet and many IDBs have comprehensive websites providing details of specific actions they have undertaken. In addition to internet-based research, this study has involved a high level of engagement with IDBs and associated organisations. An initial email was sent to 36 groups/amalgamations and independent IDBs on 20 March 2013. Eight IDBs responded expressing an interest in discussing how they manage water. Positive responses to the email were followed up to arrange a telephone discussion (for those wanting to be contacted by telephone) or further email contact (for those preferring email communication). Five TAG members also responded positively to the initial email and were subsequently contacted via telephone or email, depending upon their preference. Online research using IDB websites led to the identification of specific IDBs undertaking activities to adapt to the effects of climate change. Where these IDBs had not responded to the initial email they were sent a follow up email with more detailed RPA | i questions. Contact was also made with the Environment Agency in relation to the catchment-based approach and the Association of Drainage Authorities (ADA). Current and future risks Current risks to IDBs can be considered under several main categories: Too much water: this category incorporates the risks of flooding and waterlogging, poor water quality and damage to infrastructure; Too little water: including drought, poor water quality and damage to infrastructure; External influences: these cover development (e.g. through increased surface runoff), management of watercourses and land by others, and tensions between stakeholders; Environmental and biodiversity duties: including environmental tensions, for example, when duties imposed on IDBs by environmental regulations limit the extent of maintenance work which can be performed; Other risks: these could affect the ability of IDBs to take up future opportunities and roles and include lack of funding, lack of skills and expertise and management of assets. The extent to which these risks may change in the future is partly dependent on climatic changes. Precipitation is one of the key drivers for many of the risks. Although the annual precipitation levels for England are generally expected to decrease when compared with the UKCP09 baseline time period (1961-1990), there are areas and hence IDB districts where increased precipitation may occur under the high emissions scenario, for example, Earby and Salterforth IDD and Broads IDB. However, when looking at changes in summer precipitation levels, all IDB districts are expected to experience decreases, with levels predicted to decrease by around 17% in Axe Brue IDB and Parrett IDB. Since some IDBs are expected to experience increased annual precipitation, but decreased summer precipitation, this suggests that management of extreme conditions may become the norm. The level of precipitation feeds into many other risks which may influence IDB activities (with all predictions based on the high emissions scenario): Decreased annual river flows in some IDB districts (e.g. March East IDB, Rawcliffe DB) may bring opportunities in relation to drought management, for example, the creation of storage reservoirs and the need to adopt flexible water levels; Changes in precipitation levels combined with greater population pressure has implications for the proportion of abstracted water which is used for public water supply (PWS). IDBs which may experience increased PWS abstraction include the Axe Brue IDB, North Somerset Levels IDB and Black Sluice IDB. Opportunities associated with this risk include the transfer of water within and between IDBs, and the promotion of rainwater capture/storage and water recycling; Greater pressure on resources along with decreased precipitation could increase the risk of poor water quality in some districts (e.g. Norfolk Rivers IDB). Opportunities to mitigate this risk include moving water around to avoid stagnation; this is likely to be more relevant to larger IDBs, and also ones which have pumped catchments; and Changes in rainfall can affect the risk of urban flooding. Districts such as Black Sluice IDB, South Holland IDB and Bedfordshire & River Ivel IDB have a higher risk of urban flooding by the 2050s. Opportunities include the use of telemetry and upgrading