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Title: Management Strategies and Mitigation Measures Required to Deliver WFD for Impoundments: Volume 1 Preliminary Guidance Document
Author: Edinburgh Sniffer:
Document Type: Monograph
Annotation: Environment Agency Project ID:EAPRJOUT_1407, Representation ID: 469, Object ID: 2563
WFD29: Management Strategies and Mitigation Measures required to deliver the Water Framework Directive for Impoundments Project funders/partners: SNIFFER; Scottish Environment Protection Agency (SEPA); and Environment Agency (EA). Background to research The implementation of the EC Water Framework Directive (WFD) requires the development of new approaches and methodologies by the competent authorities in the United Kingdom. One of these requirements involves developing procedures to ensure the adequate mitigation of the negative impacts created by the construction and operation of impoundments. Any activity to mitigate the environmental impact of an impoundment must reconcile the protection of the local aquatic ecology with the socioeconomic benefits of impoundments and must fit within the overall river basin management planning process. Objectives of research The Objective of the project is to provide a Guidance Document which presents a user friendly guide for identifying best practice and cost-effective management strategies and mitigation measures for potential application to impoundments for hydro-power, flow regulation and water supply in order to meet the requirements of the Water Framework Directive in the UK. Key findings and recommendations The initial international review of impoundment management practices provided a legislative, planning, management and regulatory context for impoundments across five countries (Norway, France, Germany, Australia and USA) and identified typical and good practice mitigation measures. The review found that the licensing procedures in all countries were broadly similar. A two tiered approach to licensing, Environmental Impact Assessments for large impoundments and consultation with statutory and nonstatutory bodies were evident in all countries and the majority of the countries applied the concept of time-limited licensing and the incorporation of conditions in the license to mitigate impacts on the surrounding environment. A preliminary analysis of the mitigation techniques tried and tested by the five different countries showed that a substantial number are commonly used by all (e.g. compensation flows, fish passes, fish screens and measures to improve dissolved oxygen levels and maintain natural temperatures). Novel approaches were also identified (e.g. salt interception systems close to the coast in Australia, fish friendly turbines to prevent fish damage in USA, fish passes specifically for eels and a retaining weir dam to maintain water levels in an isolated area of the impounded water (Norway)). The key elements of the Guidance Document are: a a a a a a a a step-by-step approach a from defining the drivers and pressures on a system to identifying a potential solution or combination of cost-effective solutions; a set of ten Guidance Sheets, which cover the main environmental / management issues facing impoundment management (including topics such as hydro-peaking flows, fish migration etc.), cross-referenced to the mitigation measures database and the conceptual models; a spreadsheet of more than 100 practical mitigation measures and management strategies that could be considered; a spreadsheet of the potential indicative cost of those measures and strategies (where known); consideration of the broader environmental and technical issues associated with the implementation of the mitigation measures and management strategies (e.g. flood management, social, recreational and navigation implications etc.); conceptual models of impoundments for hydropower, flow regulation and water supply in the UK; and a comprehensive reference list for further information on individual techniques and strategies. Additional discussion is also provided on: a a a the construction and decommissioning of impoundments; the impacts of impoundments on sustainable flood management practices; and considerations for impoundments associated with coastal and transitional waters. The Guidance Document has been prepared in the light of: a a a a an international review of best practice mitigation measures and management strategies; a Steering Group of experts within the Scottish Environment Protection Agency (SEPA) and the environment Agency (EA); technical experts on the project team from a wide range of disciplines; a workshop with key stakeholders (including impoundment managers, environmental consultees, British Dam Society and SEPA / EA licensing officers). The Guidance Document has been amended in light of recommendations made following trials by SEPA / EA licensing officers and private sector impoundment managers on the River Dee (Wales) and the Glendevon (Scotland). The principal users of this guidance are envisaged to be the regulatory authorities (particularly SEPA and EA water resources licensing officers) and impoundment managers (private and public sector). The preliminary and final document can be used when: a a considering what conditions to include when licensing impoundment structures under the new licensing regime (in Scotland this is anticipated at the end of 2005); undertaking reviews of existing impoundment licences under the requirements of the WFD. It is intended that the methodology suggested in this preliminary guidance document will enrich the discussion of alternatives in public decision-making. It is important to note that the document contains the best recommendations of the consultants and does not necessarily represent the official views of SEPA and the EA. Key Words W ater Framework Directive; impoundments; mitigation measures; cost effectiveness. CONTENTS OF VOLUME 1 Page 1
Publisher: Environment Agency
Subject Keywords: Water framework directive; Regulation; Wfd; Impoundments; Mitigation measures; Cost effective
Extent: 135
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