Drought Plan May 2019 Statement from Security Manager: I certify that I have reviewed the drought plan, and can confirm it does not contain any information that would compromise national security interests. I also confirm the plan does not contain any information that may be considered commercially confidential. Barry Hayes Emergency Planning and Security Manager PAGE i Drought Plan May 2019 CONTENTS EXECUTIVE SUMMARY ............................................................................... XI 1 INTRODUCTION ................................................................................. 16 1.1 OVERVIEW OF DROUGHT PLANNING PROCESS ....................................... 16 1.1.1 Regulatory background ............................................................. 16 1.2 SOUTH EAST WATER BACKGROUND INFORMATION ................................ 18 1.2.1 Water resources planning ......................................................... 18 1.2.2 The water supply area .............................................................. 23 1.3 BASELINE WATER RESOURCES SITUATION AND LEVELS OF SERVICE ........ 23 1.4 CONSULTATION ON THE DROUGHT PLAN ............................................... 24 1.4.1 Pre-draft drought plan preparation consultation ........................ 24 1.4.2 Consultation on the draft drought plan and the statement of response ................................................................................... 25 1.5 STRUCTURE OF THE DROUGHT PLAN DOCUMENT ................................... 25 2 DROUGHT MONITORING AND TRIGGERS ..................................... 27 2.1 TRIGGER ASSESSMENT AND DROUGHT ACTION LEVELS .......................... 27 2.2 STAGE 1: GROUNDWATER TRIGGERS ................................................... 28 2.3 STAGE 1: SURFACE WATER TRIGGERS ................................................. 31 2.4 STAGE 1: RECHARGE TRIGGERS .......................................................... 32 2.5 STAGE 1: DEMAND TRIGGERS.............................................................. 36 2.6 STAGE 2: OVERRIDE TRIGGERS FOR BULK SUPPLY AND SHARED USE ...... 37 2.7 STAGE 2: DROUGHT TRIGGER MATRIX .................................................. 38 2.8 DATA SOURCES AND ARRANGEMENTS .................................................. 43 2.9 ADDITIONAL HYDROMETRIC DROUGHT MONITORING ............................... 44 2.10 FORECASTING .................................................................................... 44 2.11 STAGE 3: LINK TO ACTIONS ................................................................. 45 3 DROUGHT MANAGEMENT ACTIONS .............................................. 46 3.1 DEMAND-SIDE ACTIONS ....................................................................... 46 3.1.1 Water conservation campaigns and calls for voluntary restraint (DAPD1) ................................................................................... 46 3.1.2 Operational works to reduce demand (DAPD2) ........................ 47 3.1.3 Background to the legislation and guidance for restricting customers’ water use ................................................................ 48 3.1.4 Temporary use bans (DAPD3) .................................................. 50 3.1.5 Restrictions on uses of water through a Drought Order (DAPD4) 58 3.2 SUPPLY-SIDE ACTIONS ........................................................................ 61 3.2.1 Operational works (DAPS1) ...................................................... 61 3.2.2 Infrastructural connectivity and source improvements (DAPS2) and disused sources (DAPS3) .................................................. 62 3.2.3 Shared resources and bulk transfer agreements (DAPS4 agree extensions, and DAPS5 new agreements) ............................... 63 3.2.4 Potential drought permit (DAPS6) and drought order sites (DAPS7) .................................................................................... 71 PAGE ii Drought Plan May 2019 3.2.5 Emergency drought planning procedures (DAPS8) .................. 80 3.2.6 Emergency drought orders (DAPS9) ........................................ 80 3.3 DROUGHT ACTIONS SUMMARY ............................................................. 82 4 ENVIRONMENTAL IMPACTS ............................................................ 90 4.1 INTRODUCTION ................................................................................... 90 4.2 ASSESSING THE RISKS TO THE ENVIRONMENT ....................................... 91 4.3 ENVIRONMENTAL ASSESSMENT OF DROUGHT PERMITS/ORDERS ............. 93 4.3.1 The River Ouse drought permits/orders (DAPS6) ................... 113 4.3.2 The River Cuckmere drought permit/order (DAPS6) .............. 126 4.3.3 The Chasewood drought permit/order (DAPS6) ..................... 133 4.3.4 The Balcombe drought permit/order (DAPS6) ........................ 134 4.3.5 The Hackenden drought permit/order (DAPS6) ...................... 136 4.3.6 The Southlands and Oakland’s licence drought permit/order (DAPS6) .................................................................................. 137 4.3.7 The Halling No.8 drought permit/order (DAPS6) ..................... 139 4.4 ENVIRONMENTAL MONITORING AND DATA PROVISION ........................... 143 4.4.1 Baseline monitoring requirements for all River Ouse Drought Permit sites ............................................................................. 143 4.4.2 Baseline monitoring requirements for the River Cuckmere drought permit/order ............................................................................ 147 4.4.3 Summary baseline monitoring requirements for all drought permit/order sites .................................................................... 147 4.4.4 Monitoring requirements during drought permit/order operation. 151 4.5 MITIGATION MEASURES ..................................................................... 155 4.5.1 General measures .................................................................. 155 4.5.2 Ouse ....................................................................................... 155 4.5.3 Cuckmere, and Sedlescombe ................................................. 159 4.5.4 Remaining groundwater abstraction sites ............................... 159 4.5.5 Working in partnership with key stakeholders ......................... 159 4.5.6 Post drought ........................................................................... 160 4.5.7 Longer term monitoring recommendations during drought permit/order operation............................................................. 160 5 IMPACTS ON THE COMMUNITY .................................................... 161 5.1 INTRODUCTION ................................................................................. 161 5.2 ASSESSING THE IMPACTS TO THE COMMUNITY .................................... 161 6 MANAGEMENT AND COMMUNICATIONS STRATEGY ................ 168 6.1 MANAGEMENT STRUCTURE ............................................................... 168 6.1.1 Introduction ............................................................................. 168 6.1.2 Drought management team roles and responsibilities ............ 168 6.2 COMMUNICATIONS PLAN ................................................................... 170 6.2.1 Introduction ............................................................................. 170 6.2.2 Drought communications management .................................. 172 6.2.3 Objectives ............................................................................... 172 6.2.4 Target audiences .................................................................... 172 PAGE iii Drought Plan May 2019 6.2.5 Working in partnership during drought .................................... 177 6.2.6 Communication channels ........................................................ 179 6.2.7 Drought Communication Action Plan ...................................... 179 6.2.8 Evaluation ............................................................................... 201 7 POST DROUGHT ACTIONS ............................................................ 202 7.1 LIFTING INTERVENTION OPTIONS AND DECLARING END OF THE DROUGHT ...................................................................................................... 202 7.2 CONSULTATION DURING DROUGHT RECESSION ................................... 202 7.3 POST DROUGHT REVIEW .................................................................. 203 8 TESTING THE PLAN ........................................................................ 205 8.1 TESTING AGAINST DROUGHT SCENARIOS ............................................ 207 8.1.1 Short-term drought (2003) ...................................................... 207 8.1.2 Medium duration, multi season drought (1995-1997) ............. 211 8.1.3 Long term drought (2003-2006) .............................................. 217 8.1.4 Two dry winter drought (2010-2012) ....................................... 222 8.1.5 Overall findings from the historic scenarios ............................ 227 8.1.6 Historic scenario testing conclusion ........................................ 228 8.2 TESTING AGAINST A RANGE OF ALTERNATIVE DROUGHT SCENARIOS ...... 228 8.2.1 Summary of worst historic, severe and extreme drought scenarios 240 8.3 TESTING AGAINST A THIRD DRY WINTER DROUGHT SCENARIO ............... 243 8.4 CONCLUSIONS AND LINKAGES WITH OUR WATER RESOURCES MANAGEMENT PLAN ..............................................................................................