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Guidance Document on the Application of Water Balances for Supporting the Implementation of the WFD

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Guidance Document on the Application of Water Balances for Supporting the Implementation of the WFD Technical Report - 2015 - 090 Guidance document on the application of water balances for supporting the implementation of the WFD Final – Version 6.1 – 18/05/2015 Environment Europe Direct is a service to help you find answers to your questions about the European Union New freephone number: 00 800 6 7 8 9 10 11 A great deal of additional information on the European Union is available on the Internet. It can be accessed through the Europa server (http://ec.europa.eu). Luxembourg: Office for Official Publications of the European Communities, 2015 ISBN 978-92-79-52021-1 doi: 10.2779/352735 © European Union, 2015 Reproduction is authorised provided the source is acknowledged. Guidance document on the application of water balances for supporting the implementation of the WFD Final – Version 6.1 – 18/05/2015 Table of content 1. INTRODUCTION ....................................................................................................... 4 1.1. Context .............................................................................................................. 4 1.2. A guidance: what for? ....................................................................................... 7 1.3. Guide to the reader ............................................................................................ 9 2. KEY COMPONENTS OF WATER BALANCES ................................................... 11 2.1. The key components of the hydrological cycle ............................................... 11 2.2. From water balance to a detailed list of water quantity related parameters used to support policy making ........................................................................ 15 3. KEY ISSUES IN DEVELOPING WATER BALANCES ....................................... 24 3.1. Developing water balances…. at the right scale ............................................. 24 3.2. Data sources (quality) and uncertainties ......................................................... 25 3.3. Correctly identifying water availability and accounting for ecological needs (links to e-flows) ............................................................................................. 27 4. APPLYING WATER BALANCES IN PRACTICE ................................................ 31 5. USING WATER BALANCES FOR SUPPORTING WATER MANAGEMENT .. 39 5.1. Supporting the characterization of river basins and the identification of key water management issues ................................................................................ 39 5.2. Supporting the selection of measures for the WFD PoM ................................ 39 5.3. Target setting and allocation ........................................................................... 41 5.4. Adapting to climate change ............................................................................. 42 5.5. Identifying room for improvement in resource efficiency .............................. 42 5.6. Contributing to informing and reporting on water policy implementation ..... 43 6. EXPANDING THE PHYSICAL WATER BALANCE FOR ADDRESSING COMPLEMENTARY WATER MANAGEMENT ISSUES ................................... 45 6.1. Expanding water balance to account for water quality ................................... 45 6.2. Integrating the economic dimensions of water use and management ............. 45 6.3. EEA and Eurostat related works ..................................................................... 51 7. RECOMMENDATIONS AND CONCLUSIONS ................................................... 53 8. LIST OF REFERENCES .......................................................................................... 55 ANNEXES ........................................................................................................................ 59 ANNEX I – ILLUSTRATING THE APPLICATION OF WATER BALANCES .......... 59 Case study #1: Ali-Efenti River Basin, Greece (ABOT project, DG ENV) ............. 59 Case study #2: Tiber River Basin, Italy (ABOT project, DG ENV) ......................... 62 Case study #3: Vit River Basin, Bulgaria (ABOT project, DG ENV) ...................... 65 Case study #4: Mulde River Basin, Germany (ABOT project, DG ENV) ............... 68 Case study #5: Arno River Basin, Germany (PAWA project, DG ENV) ................. 71 Case study #6: Slovenia ............................................................................................ 77 2 Case study #7: The Jeziorka River Catchment, Poland ............................................ 82 Case study #8: Use of water resource balance as a tool for the assessment of the quantitative relation between water requirements (including the minimum balance discharge) and water resources – example from Slovakia ................. 85 1.1 Objective of the Case study ............................................................................. 85 1.2 Policy and management context ...................................................................... 85 2 DETAILED INFORMATION .................................................................................. 85 2.1 Practical Tasks (in case of methods and/or procedures) ................................. 85 2.2 Temporal and spatial scales ............................................................................. 86 2.3 Type of analysis or tool ................................................................................... 86 2.4 Information and data requirements.................................................................. 91 2.5 Testing of results ............................................................................................. 93 2.6 Current application of the method/initiative ................................................... 93 2.7 Learned lessons - Conclusions – Recommendations for application within the concept of Eflows ...................................................................................... 94 Contact information................................................................................................... 94 ANNEX II – KEY METHODOLOGICAL LESSONS FROM THE EU-FUNDED PILOT STUDIES ...................................................................................................... 96 ANNEX III –COMPARISON BETWEEN THE “SEEAW ASSET ACCOUNTS” AND THE “WATER BALANCE” COMPONENTS ............................................. 120 3 1. INTRODUCTION 1.1. Context The vital importance of water for supporting the functioning of ecosystems while contributing at the same time to economic development is widely recognized in all parts of Europe today. Historically, most attention has been given to water quality issues as illustrated by the early European Union (EU) water directives developed during the 1970s and the early 1980s that aimed at ensuring the good quality of waters used for different purposes (e.g. for drinking, water swimming, fishing, etc.). With the increasing imbalance between water supply and water demand 1in many parts of Europe, including also some in parts of Northern Europe [1], potentially exacerbated by changes in climate during the past few decades, water availability and water scarcity has progressively emerged as a key issue in national and EU water policy making and implementation, as illustrated in the policy objectives of different Directives and Communications (Table 1). Table 1. Policy objectives related to water availability in different directives, working documents, communications and strategies. EU Directive/Communication/ Strategy Policy Objective EU Water Framework Directive (WFD) Ensure a good quantitative status of groundwater bodies; 2000/60/EC, daughter directives (2000) Achieve good ecological status of surface water bodies (including in terms of [2], and guidance documents within the supporting environmental river flow requirements); Common Implementation Strategy. Identify significant pressures from abstraction (Art. 5). EC Communication “Addressing the Encourage Member States (MS) to identify river basins which face quasi- challenge of water scarcity and drought permanent or permanent water stress or scarcity; in the European Union” Improve drought risk management; (2007) [3] Improve knowledge and data collection. EC Communication “Blueprint to Put quantitative water management on a much more solid foundation Safeguard Europe’s Water” (2012) [4] (including identification of the ecological flow –i.e. the amount of water required for the aquatic ecosystem to continue to thrive and provide services) and address the issue of over-allocation at the river basin scale; Recognize that water quality and quantity are intimately related within the concept of good status; Develop water efficiency targets for river basins which are (or are projected to be) water stressed, on the basis of water stress indicators developed in the Common Implementation Strategy (CIS) process and applied at river basin level; Implement Water Accounts at river basin and sub-catchment level: they can tell water managers how much water flows in and out of a river basin and how much water can realistically be expected to be available before allocation takes place; Identify and reduce of illegal abstraction/impoundments. EU Strategy on Adaptation to Climate Build a solid knowledge base on the impact and consequences of climate Change [5]. change for EU water resources as a basis for developing sound adaptation EC Communication “White Paper: strategies for water. (Water resources are directly impacted by climate change, and the management of these resources affects the vulnerability of 1 ‘Water demand’
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