Water Resources in Anglia
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NRA Anglia 122 WATER RESOURCES IN ANGLIA information Centre H ead Office Class No ... A c c e s s * 0 0 A SUSTAINABLE STRATEGY FOR NRA National Rivers Authority SECURE WATER SUPPLIES AND A Anglian Region BETTER WATER ENVIRONMENT SEPTEMBER 1994 For further information please contact: The W ater Resources Manager The National Rivers Authority (Anglian Region) Kingfisher House Goldhay Way Orton Goldhay Peterborough PE2 5ZR Tel: (0733)371811 Fax:(0733)231840 ■ Catchment Office Q Headquarters ** The National Rivers Authority is committed to the principles of stewardship and sustainability. In addition to pursuing its statutory responsibilities as Guardians of the Water Environment, the NRA will aim to establish and demonstrate wise environmental practice throughout all its functions.99 20% virgin, 40% pre-consumer waste, 40% post-consumer waste - totally chlorine free paper. 2 ----------- ----------------------------------------------------- < C X i FOREWORD Water is vital to life. We are blessed in this country with ample rain - more than enough to sustain a healthy water environment and to meet human needs. But the rain falls unevenly, both in time and place. Our water resources, and the uses we make of them, must be managed sustainably to ensure that water is available, both for people and for rivers and wetlands, in the right quantities at the right times and places, and at the right cost. This is not a job for the National Rivers Authority (NRA) alone. Water undertakers, industry, farmers, environmental interests, planning authorities and many others have parts to play. What is needed is an overall framework within which all can work to the common good. Our National Water Resources Development Strategy sets out such a framework at the broad national scale. This Regional Strategy deals in detail with the water resources of the Anglian Region. Our vision of the future Our rivers and our wetlands are a precious heritage. However, in this Region they are almost totally unnatural because they have been changed by man down the centuries. There is great scope to re-create a better water environment. However, Anglia has a water problem. In summer evaporation exceeds rainfall. This dries out the soil and depletes water resources. The six million of us who live between the Thames and the Humber rely on a complex water network (part natural, part man-made) to store and distribute winter water both to our rivers and to our taps. A run of dry winters strains that network, as we have recently seen. Such droughts are a feature of our climate, and with a growing population actions are needed to provide security against an uncertain future. Those actions should be planned, not piecemeal; they should give value for money; they should encompass both sustainability and the precautionary principle; / 1 \ they should improve the water environment, not impair it. The NRA aims to achieve the right balance between the needs of the environment and t those of abstractors; or in short:- Secure water supplies and a better water environment r t - n - n We see these twin objectives as equally important and we intend to achieve them both. NATIONAL LIBRARY & INFORMATION SERVICE HEAD OFFICE Rio House, Waterside Drive, Aztec West, Almondsbury, Bristol BS32 4UD ENVIRONMENT AGENCY CONTENTS OBJECTIVES OF THE THE NATIONAL ANGLIAN REGIONAL CONTEXT STRATEGY THE PRINCIPLES OF WATER MANAGEMENT ANGLIA'S WATER THE WATER RESOURCES ENVIRONMENT AND ITS NEEDS DEMANDS THE HUMAN POPULATION AND ITS NEEDS ADDITIONAL WATER NEEDS THE OPTIONS FOR SAVING WATER THE AVALABILITY OF WATER TO MEET THE OPTIONS FOR FUTURE NEEDS RE-ALLOCATING WATER OPTIONS THE OPTIONS FOR SECURE WATER SUPPLIES ASSESSING THE CHOICES THE OPTIONS FOR A BETTER WATER ENVIRONMENT THE STRATEGY A BLUEPRINT FOR SECURE WATER SUPPLIES THE FUTURE AND A BETTER WATER ENVIRONMENT PAGE C H A PTER 1 INTRODUCTION CH A PTER 2 THE NATIONAL CONTEXT 10 The NRA Water Resources Strategy The National Water Resources Development Strategy Changing Water Use CH A PTER 3 OBJECTIVES OF THE ANGLIAN REGIONAL STRATEGY 11 CH A PTER 4 THE PRINCIPLES OF WATER MANAGEMENT 12 The needs of the Water Environment Sustainability The Precautionary Principle Meeting Reasonable Human Needs Levels of Service Demand Management Cost General Ground Rules for the Strategy Control of Abstractions The Role of Development Planning CHAPTER 5 ANGLIA’S WATER RESOURCES 16 Description Surface Water Resources Groundwater Resources The Quality of Water Resources Climate Change Development of Water Resources Water Sourceworks Imports to the Region CHAPTER 6 THE WATER ENVIRONMENT AND ITS NEEDS 26 Water for the Soil Water for Wetlands Water for Lakes Water for Rivers Water for Estuaries CHAPTER 7 THE HUMAN POPULATION AND ITS NEEDS 33 Population Licensed Water Use Public Water Supply Agriculture Power Generation Other Industry Navigation Fisheries and Recreation Effluent Dilution CHAPTER 8 ADDITIONAL WATER NEEDS 38 Public Water Supply Agriculture and Industry Environmental Deficits - Rivers Environmental Deficits - Wetlands Environmental Deficits - Effect on water users Summary of Additional Needs CHAPTER 9 AVAILABILITY OF WATER TO MEET FUTURE NEEDS 43 Licensing Policy The Current Availability of Raw Water The Future Availability of Raw Water CHAPTER 10 THE OPTIONS FOR SAVING WATER 44 Using Water Wisely Current Demand Management in Anglia The Means of Demand Management The Effects of Demand Management on the Environment CHAPTER 11 THE OPTIONS FOR RE-ALLOCATING WATER 48 Under-used and inefficiently’ used licences Environmental Allocations Incentive Charging Consultation CHAPTER 12 THE OPTIONS FOR SECURE WATER SUPPLIES 50 Minor Local Sources Groundwater Surface Water Use of Effluents Imports ‘Esoteric’ Options C H A PT E R 13 THE OPTIONS FOR A BETTER WATER ENVIRONMENT 64 Introduction Improving our Wetlands Improving our Rivers Other Environmental Improvements C H A PT E R 14 ASSESSING THE CHOICES 68 Introduction Summary of Environmental Needs Summary of Additional Human Needs The Scope for Improving the Environment The Scope for Demand Management The Scope for Reallocating Water The Need for Additional Water The Development Options The Results of Public Consultation Disentangling the Choices C H A PT E R 15 THE STRATEGY 79 General Policies for Managing Water Resources Policies for Controlling the Demand for Water Policies for Allocating (and re-allocating) Water Actions to Achieve a Better Environment Actions to Achieve Secure Water Supplies Investigations CH A PTER 16 THE FUTURE 84 TABLES 1 Summary of major surface water resources 2 Summary of groundwater resources 3 Summary of PWS sourceworks reliable outputs 4 H ands-off flows 5 Hands-off flows to tide 6 Population by Water Company Areas 7 Licensed abstractions 8 Summary of demand forecasts 9 Additional Water Needs 10 Rivers and wetlands suggested to be suffering from over-abstraction 11 Potential Water Resources Development Options 12 Trent Transfer Options - Summary 13 Predicted Additional Human Needs FIGURES 1 Map of Region, with Water Network 2 High Rainfall and Dry Periods 3 Major Aquifer Outcrops and Average Effective Rainfall 4 What Happens to our Rainfall? 5 Where Does the Water Go? 6 What Effects Will Increasing Demands Have? 7 So What’s the Problem? 8 The Availability of Groundwater 9 Concept of River Flow Objectives 10 Public Water Supply - demand 11 Public Water Supply Total Leakage 12 ‘Low Flow’ Rivers and Wetlands 13 Potential Strategic Transfer Links 14 ‘Water Resource’ Areas 15 Groundwater Resources and Licensed Abstractions by Counties 16 Potential Area of Benefit from Bradley/Feltwell Reservoirs 1.1 Groundwater Balance Methodology 1.2 The Allocation of Groundwater to Rivers 3.1 Public Water Supply Unmeasured Water Delivered 5.2 Components of Public Water Supply Demand 7.1 Demand Forecasts for Spray Irrigation REFERENCES 85 ANNEXES A88 1 Consultees 2 Glossary of Terms 3 Detail of Surface W'ater Resources 4 Detail of Groundwater Resources 5 Public Water Supply SROs 6 Public Water Supply Demand Forecasts 7 Direct Water Use Forecasts 8 Derivation of Deficit Forecasts for Direct Water Use 9 The Availability of Water 7 Chapter 1 - INTRODUCTION The Anglian Region (Figure 1) is the driest in Britain. It has the fastest growing population and the fastest rising water demands, particularly for public supply and irrigation. Its water environment, though far from natural, is a precious asset. 0 < 1 From 1988 - 1992 Anglia experienced its worst drought in a century of records (Ref 1 and Figure 2). There were hosepipe bans in some areas, more severe restrictions in a few, and local bans on irrigation. Rivers and groundwater levels were low, causing some environmental damage. The fact that almost 6 million people living in the driest part of the country survived such a drought with so little disruption is due to a comprehensive network of water storage and transfers. This network has evolved over the centuries in step with rising water use. It taps into all our major rivers and most of our groundwater A resources. It is augmented by transfers from outside the region. Figure 1 * Major Elements of Regional Water Resource System Treated Water Supply ► Raw Water Transfer Boundary of Fens Regulated River Regulated River (Potential) Trent-Withai PWS Reservoir Aruholme Schem e Underlying Aquifer Groundwater Well Field Groundwater Well Field (Potential) O G w ash -G le n t T ransfer Norwich n ~ n _ n Oundlt Transfers to \ Middle Level Alton Reservoir Ely O u se^ 1 ao Three' 'Colchester Essex Scheme V a lle ys W ater C om p an y Area Basildon R egion 8 Figure 2 - High Rainfall and Dry Periods E 400—1 — 400 J. l/t 3 Q-w 3 2 0 0 - —200 “5 T 5 i 0 - E 200 - — -200 j i •w o - 4 0 0 - — 400 " 5 -600 - Figure 2 shows that droughts are a regular feature of Anglia’s climate. Rising water demands and rising environmental aspirations will not be met during the next drought unless we plan for it now.