Water Cycle Study - East Devon District Council

CONTENTS
Ref EWCS April 2010
Exeter and East Devon Water Cycle Study
Executive summary.....................................................................................................................................6
1 Introduction....................................................................................................................................9
1.1 Introduction ....................................................................................................................................................................9
1.2 Background......................................................................................................................................................................9
1.3 Water neutrality...........................................................................................................................................................11
1.4 Study scope ...................................................................................................................................................................11
1.5 Evidence base................................................................................................................................................................12
2 Growth and development...........................................................................................................13
2.1 Planning policy ..............................................................................................................................................................13
2.2 Development scenarios..............................................................................................................................................14
3 The water cycle catchment ........................................................................................................19
3.1 Introduction ..................................................................................................................................................................19
3.2 River catchments and hydrology ..............................................................................................................................19
3.3 Geology..........................................................................................................................................................................22
4 Flood risk management and urban drainage............................................................................23
4.1 Introduction ..................................................................................................................................................................23
4.2 Flood risk assessments and management plans.....................................................................................................25
4.3 Development and existing flood risk.......................................................................................................................26
4.4 Impact of development on flood risk.......................................................................................................................30
4.5 Development and surface water management ......................................................................................................32
5 Environmental context ...............................................................................................................41
5.1 Environmental assets...................................................................................................................................................41
5.2 Green Infrastructure (GI) ..........................................................................................................................................42
5.3 River Quality Objectives (RQOs) ............................................................................................................................43
5.4 The Water Framework Directive ............................................................................................................................44
5.5 River Basin Management Plans..................................................................................................................................46
6 Wastewater collection, treatment, disposal and environmental quality ..............................53
6.1 Introduction ..................................................................................................................................................................53
6.2 Wastewater collection and sewerage .....................................................................................................................53
4