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Eurobodalla Shire Council Integrated Water Cycle Management Strategy IWCM Issues Paper
FINAL
14 April 2016
EUROBODALLA SHIRE COUNCIL – IWCM ISSUES PAPER
PROJECT 12-050 – EUROBODALLA IWCM STRATEGY REV DESCRIPTION AUTHOR REVIEW APPROVAL DATE
0 Draft for Council review R. Campbell K. Pratt, M. Howland M. Howland 11 Feb 2016
1 Updated with Council comments and additional data
R. Campbell M. Howland M. Howland 14 April 2016
2 Issued as final 14 April 2016
Eurobodalla Shire Council: IWCM Issues Paper
Prepared on behalf of Eurobodalla Shire Council by Hydrosphere Consulting.
Suite 6, 26-54 River Street PO Box 7059, BALLINA NSW 2478 Telephone: 02 6686 0006 Facsimile: 02 6686 0078 © Copyright 2016 Hydrosphere Consulting
EUROBODALLA SHIRE COUNCIL – IWCM ISSUES PAPER
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CONTENTS
PART A: IWCM ISSUES .................................................................................................................................... 1
1. DOCUMENT STRUCTURE ................................................................................................................ 2
2. SUMMARY OF BACKGROUND INFORMATION .............................................................................. 3
3. COMPLIANCE WITH OPERATING ENVIRONMENT REQUIREMENTS .......................................... 4
4. IWCM ISSUES .................................................................................................................................... 5
5. WATER SENSITIVE URBAN DESIGN OBJECTIVES ..................................................................... 11
6. TOTAL ASSET MANAGEMENT PLAN STATUS AND REVIEW ..................................................... 11
7. DRINKING WATER MANAGEMENT SYSTEM STATUS ................................................................ 14
8. CONSULTATION .............................................................................................................................. 14
PART B – BACKGROUND INFORMATION .................................................................................................... 16
9. ITEM 2 - INTRODUCTION ................................................................................................................ 17
9.1 Study Area ........................................................................................................................................ 17
9.2 Urban Water Systems ...................................................................................................................... 18
9.3 Current IWCM Strategy .................................................................................................................... 19
9.4 IWCM Assumptions .......................................................................................................................... 30
9.4.1 Population Growth ........................................................................................................................ 30
9.4.2 Water Demand .............................................................................................................................. 32
9.4.3 Water Availability .......................................................................................................................... 32
9.4.4 Wastewater Volumes .................................................................................................................... 34
10. ITEM 3 - OPERATING ENVIRONMENT .......................................................................................... 36
10.1 Compliance Requirements ............................................................................................................... 36
10.1.1 Legislative Requirements ............................................................................................................. 36
10.1.2 Guidelines ..................................................................................................................................... 39
10.1.3 Water Sharing Plans and Extraction Licences ............................................................................. 40
10.1.4 Environment Protection Licences ................................................................................................. 45
10.2 Situation Analysis ............................................................................................................................. 45
10.2.1 Compliance with Legislative and Contractual Requirements ....................................................... 45
10.2.2 Compliance with Guidelines ......................................................................................................... 45
10.2.3 Compliance with Environment Protection Licences ..................................................................... 46
10.2.4 Compliance with Best-Practice Requirements ............................................................................. 47
10.2.5 Performance Indicators ................................................................................................................ 47
10.2.6 Service Provision Review ............................................................................................................. 50
10.3 Levels of Service .............................................................................................................................. 53
EUROBODALLA SHIRE COUNCIL – IWCM ISSUES PAPER
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11. ITEM 4 - URBAN WATER SERVICES ..............................................................................................56
11.1 Urban Centres ...................................................................................................................................56
11.2 Water Supply Systems .....................................................................................................................71
11.2.1 Catchments ...................................................................................................................................74
11.2.2 Treatment Process ........................................................................................................................78
11.3 Sewerage Systems ...........................................................................................................................82
11.3.1 Batemans Bay Sewerage Scheme ...............................................................................................82
11.3.2 Tomakin Sewerage Scheme .........................................................................................................86
11.3.3 Moruya Sewerage Scheme ..........................................................................................................90
11.3.4 Tuross Head and Turlinjah Sewerage Scheme ............................................................................95
11.3.5 Narooma Sewerage Scheme ........................................................................................................99
11.4 Trade Waste ...................................................................................................................................104
11.5 Urban Stormwater ...........................................................................................................................105
11.6 Asset Data ......................................................................................................................................113
11.7 Pricing Signals ................................................................................................................................114
12. ITEM 5 – POPULATION AND DEMOGRAPHIC PROJECTIONS ..................................................118
12.1 Water Supply Customers ................................................................................................................118
12.1.1 Shire-Wide Data ..........................................................................................................................118
12.1.2 Existing and Historical Connections ...........................................................................................119
12.1.3 Connection Growth .....................................................................................................................128
12.1.4 Major Water Users ......................................................................................................................130
12.2 Sewerage System Connections ......................................................................................................130
12.2.1 Shire-Wide Data ..........................................................................................................................130
12.2.2 Sewerage Customers by Sewer Catchment ...............................................................................131
12.3 Unserviced Areas............................................................................................................................135
12.3.1 South Durras ...............................................................................................................................136
12.3.2 Nelligen .......................................................................................................................................136
12.3.3 Rosedale and Guerilla Bay .........................................................................................................136
12.3.4 Congo .........................................................................................................................................136
12.3.5 Bodalla ........................................................................................................................................136
12.3.6 Potato Point ................................................................................................................................137
12.3.7 Southern Villages ........................................................................................................................137
13. ITEM 6 – 30 YEAR WATER CYCLE ANALYSIS AND PROJECTION ...........................................138
13.1 Town Water Supply.........................................................................................................................138
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13.1.1 Production and Consumption ..................................................................................................... 138
13.1.2 Demand Forecast ....................................................................................................................... 146
13.2 Batemans Bay Sewerage System .................................................................................................. 152
13.2.1 Sewerage System Flows ............................................................................................................ 152
13.2.2 Influent and Effluent Flows ......................................................................................................... 155
13.2.3 Inflow Analysis ............................................................................................................................ 157
13.2.4 Forecast Biological Load ............................................................................................................ 161
13.2.5 Forecast Flows ........................................................................................................................... 162
13.3 Tomakin Sewerage System ............................................................................................................ 163
13.3.1 Sewerage System Flows ............................................................................................................ 163
13.3.2 Influent and Effluent Flows ......................................................................................................... 165
13.3.3 Inflow Analysis ............................................................................................................................ 167
13.3.4 Forecast Biological Load ............................................................................................................ 171
13.3.5 Forecast Flows ........................................................................................................................... 173
13.4 Moruya Sewerage System ............................................................................................................. 176
13.4.1 Sewerage System Flows ............................................................................................................ 176
13.4.2 Influent Flows .............................................................................................................................. 178
13.4.3 Inflow Analysis ............................................................................................................................ 181
13.4.4 Forecast Biological Load ............................................................................................................ 185
13.4.5 Forecast Flows ........................................................................................................................... 187
13.5 Tuross Sewerage System .............................................................................................................. 188
13.5.1 Sewerage System Flows ............................................................................................................ 188
13.5.2 Influent Flows .............................................................................................................................. 190
13.5.3 Inflow Analysis ............................................................................................................................ 192
13.5.4 Forecast Biological Load ............................................................................................................ 197
13.5.5 Forecast Flows ........................................................................................................................... 198
13.6 Narooma Sewerage System ........................................................................................................... 200
13.6.1 Sewerage System Flows ............................................................................................................ 200
13.6.2 Influent and Effluent Flows ......................................................................................................... 201
13.6.3 Inflow Analysis ............................................................................................................................ 203
13.6.4 Forecast Biological Load ............................................................................................................ 207
13.6.5 Forecast Flows ........................................................................................................................... 209
13.7 Unserviced Areas ........................................................................................................................... 210
13.7.1 South Durras ............................................................................................................................... 210
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13.7.2 Nelligen .......................................................................................................................................211
13.7.3 Rosedale and Guerilla Bay .........................................................................................................211
13.7.4 Congo .........................................................................................................................................211
13.7.5 Bodalla ........................................................................................................................................211
13.7.6 Potato Point ................................................................................................................................212
13.7.7 Southern Villages ........................................................................................................................212
13.8 Recycling Systems..........................................................................................................................213
13.8.1 Batemans Bay STP Recycling Scheme......................................................................................213
13.8.2 Tomakin STP Recycling Scheme ...............................................................................................216
13.8.3 Moruya STP Recycling Scheme .................................................................................................216
13.8.4 Bingie STP Recycling Scheme ...................................................................................................218
13.9 Urban Stormwater Systems ............................................................................................................221
14. ITEM 7 - EXISTING URBAN WATER SYSTEM CAPACITY AND PERFORMANCE ....................222
14.1 Town Water Supply.........................................................................................................................222
14.1.1 Secure Yield and Forecast Demand ...........................................................................................222
14.1.2 Treatment Capacity and Performance ........................................................................................224
14.1.3 Distribution System Performance ...............................................................................................228
14.1.4 Asset Condition ...........................................................................................................................229
14.2 Batemans Bay Sewerage System ..................................................................................................229
14.2.1 Collection System Capacity ........................................................................................................229
14.2.2 Treatment Capacity and Performance ........................................................................................230
14.2.3 Asset Condition ...........................................................................................................................232
14.3 Tomakin Sewerage System ............................................................................................................233
14.3.1 Collection System Capacity ........................................................................................................233
14.3.2 Treatment Capacity and Performance ........................................................................................233
14.3.3 Asset Condition ...........................................................................................................................235
14.4 Moruya Sewerage System ..............................................................................................................235
14.4.1 Collection System Capacity ........................................................................................................235
14.4.2 Treatment Capacity and Performance ........................................................................................236
14.4.3 Asset Condition ...........................................................................................................................237
14.5 Tuross Sewerage System ...............................................................................................................238
14.5.1 Collection System Capacity ........................................................................................................238
14.5.2 Treatment Capacity and Performance ........................................................................................238
14.5.3 Asset Condition ...........................................................................................................................240
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14.6 Narooma Sewerage System ........................................................................................................... 240
14.6.1 Collection System Capacity ........................................................................................................ 240
14.6.2 Treatment Capacity and Performance........................................................................................ 240
14.6.3 Asset Condition........................................................................................................................... 241
14.7 Recycling Systems ......................................................................................................................... 242
14.7.1 Batemans Bay STP Recycling Scheme ..................................................................................... 242
14.7.2 Moruya STP Recycling Scheme ................................................................................................. 243
14.7.3 Bingie STP Recycling Scheme ................................................................................................... 244
14.8 Urban Stormwater Systems ............................................................................................................ 244
14.9 Unserviced Areas ........................................................................................................................... 245
14.9.1 Private Water Supplies ............................................................................................................... 245
14.9.2 Private Sewerage Systems ........................................................................................................ 245
REFERENCES ............................................................................................................................................... 249
GLOSSARY AND ABBREVIATIONS ............................................................................................................. 252
APPENDIX 1: 2013/14 TBL REPORTS ..................................................................................................... 255
APPENDIX 2: DRAFT WSP MAPS AND REPORT CARDS: CLYDE RIVER, DEUA RIVER AND TUROSS RIVER UNREGULATED AND ALLUVIAL WATER SOURCES ..................................................................... 257
APPENDIX 3: EPA LICENCES.................................................................................................................. 259
TABLES
Table 1: IWCM Issues Paper – Check List Requirements ................................................................................. 2
Table 2: Operating Environment Compliance Summary .................................................................................... 4
Table 3: Data Gaps ............................................................................................................................................ 5
Table 4: IWCM Issues ........................................................................................................................................ 5
Table 5: Water Supply Capital Works Budget .................................................................................................. 11
Table 6: Water Supply Operation and Maintenance Budget ............................................................................ 12
Table 7: Sewerage Capital Works Budget ....................................................................................................... 12
Table 8: Sewerage Operation and Maintenance Budget ................................................................................. 13
Table 9: Urban Water Supply and Sewerage Services .................................................................................... 18
Table 10: Status of 2003 IWCM Strategy Actions ............................................................................................ 21
Table 11: Adopted Population Projection to 2031 – By Area ........................................................................... 31
Table 12: Secure Yield Estimates .................................................................................................................... 33
Table 13: Key Legislation ................................................................................................................................. 36
Table 14: Environmental Planning Instruments ............................................................................................... 38
Table 15: Relevant Urban Water Management Guidelines .............................................................................. 39
EUROBODALLA SHIRE COUNCIL – IWCM ISSUES PAPER
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Table 16: Town Water Sources and Extraction Licences ................................................................................ 40
Table 17: Draft Water Sharing Plan Rules ...................................................................................................... 42
Table 18: Environment Protection Licences .................................................................................................... 45
Table 19: Recycled Water Management Systems .......................................................................................... 46
Table 20: Details of Non-Compliances from 2012/13, 2013/14 and 2014/15 Annual Returns ....................... 46
Table 21: Required TBL Improvement Actions - Sewerage ............................................................................ 47
Table 22: Required TBL Improvement Actions – Water Supply ...................................................................... 49
Table 23: Service Provision Review ................................................................................................................ 50
Table 24: Water Supply Levels of Service ....................................................................................................... 53
Table 25: Sewerage Levels of Service ............................................................................................................ 55
Table 26: Catchment Snapshot ....................................................................................................................... 74
Table 27: Summary of Town Water Catchment Flows and Extraction ............................................................ 77
Table 28: Environment Protection Licence Conditions – Batemans Bay Sewerage Scheme ........................ 86
Table 29: Environment Protection Licence Conditions - Tomakin Sewerage Scheme ................................... 90
Table 30: Environment Protection Licence Conditions - Moruya Sewerage Scheme ..................................... 94
Table 31: Environment Protection Licence Conditions - Tuross Sewerage Scheme ...................................... 99
Table 32: Environment Protection Licence Conditions – Narooma Sewerage Scheme ............................... 104
Table 33: Trade Waste Dischargers – Large Industrial and Prescribed Pre-treatment ................................ 104
Table 34: Summary of Stormwater Catchment Characteristics .................................................................... 105
Table 35: Asset Values – Sewer (2014/15 $’000) ......................................................................................... 113
Table 36: Asset Values – Water Supply (2014/15 $’000) .............................................................................. 114
Table 37: Asset Values – Stormwater (2014/15 $’000) ................................................................................. 114
Table 38: Water Supply and Sewerage Charges – 2015/16 ......................................................................... 115
Table 39: Number of Assessments by Reservoir Zone ................................................................................. 119
Table 40: Holiday Rental Accommodation .................................................................................................... 125
Table 41: Caravan Park Accommodation ...................................................................................................... 126
Table 42: Hotel and Motel Accommodation ................................................................................................... 126
Table 43: Commercial Visitor Accommodation Capacity .............................................................................. 126
Table 44: Connected Resident Population by Reservoir Zone ..................................................................... 127
Table 45: Projected Private Dwellings ........................................................................................................... 128
Table 46: Adopted Dwelling Projection .......................................................................................................... 129
Table 47: Initial Sewer ET Loads ................................................................................................................... 132
Table 48: Residential Development Served by Sewer Schemes – Detached Dwellings .............................. 133
Table 49: Residential Development Served by Sewer schemes – Semi-Detached Dwellings ..................... 133
EUROBODALLA SHIRE COUNCIL – IWCM ISSUES PAPER
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Table 50: Residential Development Served by Sewer Schemes – Flats ....................................................... 134
Table 51: Growth in ETs by Sewer Scheme .................................................................................................. 134
Table 52: Growth in Total Peak EP by Sewer Scheme .................................................................................. 135
Table 53: Properties without Town Water Supply and/or Sewer in each Village ........................................... 135
Table 54: Permanent and Peak Population and Dwelling Estimates – Rosedale and Guerilla Bay Sewerage Scheme........................................................................................................................................................... 136
Table 55: Population and Dwelling Projection – Bodalla Sewerage Scheme ................................................ 137
Table 56: Population and Dwelling Projection – Southern Villages ............................................................... 137
Table 57: Non-Revenue Water ....................................................................................................................... 140
Table 58: Non-Residential Demand by Sector ............................................................................................... 146
Table 59: Annual Dry Year Demand Projection ............................................................................................. 148
Table 60: Annual Average Year Demand Projection ..................................................................................... 149
Table 61: Peak Day Demand Projection ........................................................................................................ 150
Table 62: Water Demands.............................................................................................................................. 151
Table 63: Parks, Ovals and Reserves Demands ........................................................................................... 151
Table 64: Basis for Equivalent Populations – Batemans Bay Sewerage System .......................................... 152
Table 65: Summary of ET and EP Loading for Batemans Bay Existing Serviced Area ................................ 153
Table 66: Calculated Peak and Non-Peak – Batemans Bay Sewerage Catchments .................................... 154
Table 67: Batemans Bay STP Hydraulic Inflow (kL/day) ............................................................................... 158
Table 68: Batemans Bay STP Raw Sewage Characteristics ......................................................................... 161
Table 69: Batemans Bay STP Load Projection (ADWF, L/s) ......................................................................... 163
Table 70: Basis for Equivalent Populations – Tomakin Sewerage System ................................................... 164
Table 71: Summary of ET and EP Loading for Tomakin Existing Serviced Area .......................................... 164
Table 72: Calculated Peak and Non-Peak – Tomakin Sewerage Catchments .............................................. 165
Table 73: Tomakin STP Inflows – Non-Peak ................................................................................................. 167
Table 74: Tomakin STP ADWF per ET and per EP ....................................................................................... 168
Table 75: Summary of Tomakin STP Inflows (2011 – 2015) ......................................................................... 168
Table 76: Tomakin STP Influent Quality ......................................................................................................... 171
Table 77: Tomakin Sewerage System Peak EP Load ................................................................................... 172
Table 78: Tomakin Sewerage System ET Load ............................................................................................. 174
Table 79: Basis for Equivalent Populations – Moruya Sewerage System ..................................................... 176
Table 80: Summary of ET and EP Loading for Moruya Existing Serviced Area ............................................ 177
Table 81: Calculated Peak, Non-Peak and Design Flows – Moruya Sewerage Catchments ........................ 177
Table 82: Moruya STP Inflows – Non-Peak ................................................................................................... 181
Table 83: Moruya STP Non-Peak ADWF per ET and per EP ........................................................................ 181
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Table 84: Summary of Moruya STP Inflows (2011 – 2014) .......................................................................... 182
Table 85: Moruya STP Influent Quality .......................................................................................................... 185
Table 86: Moruya Sewerage System Non-Peak EP Load ............................................................................ 186
Table 87: Basis for Equivalent Populations – Tuross Head and Turlinjah Sewerage System ...................... 189
Table 88: Summary of ET and EP Loading for Tuross Head and Turlinjah Catchments .............................. 189
Table 89: Calculated Peak, Non-Peak and Design Flows – Tuross Head and Turlinjah Sewerage Catchments .................................................................................................................................................... 190
Table 90: Comparison of ADWF Monitoring – Bingie STP ............................................................................ 193
Table 91: Bingie STP Inflows – Non-Peak .................................................................................................... 193
Table 92: Tuross Head STP ADWF per ET and per EP ............................................................................... 193
Table 93: Summary of Tuross Head STP Inflows (2011 – 2014) .................................................................. 194
Table 94: Bingie STP Influent Quality ............................................................................................................ 197
Table 95: Tuross Sewerage System Peak EP Load ..................................................................................... 197
Table 96: Tuross Sewerage System ET Load ............................................................................................... 199
Table 97: Kianga STP Sewage Flow ............................................................................................................. 203
Table 98: Kianga STP EP Contributions ....................................................................................................... 203
Table 99: Kianga STP Inflows – Non-Peak ................................................................................................... 204
Table 100: Kianga STP ADWF per ET and per EP ....................................................................................... 204
Table 101: Summary of Kianga STP Inflows (2011 – 2015) ......................................................................... 204
Table 102: Kianga STP Raw Sewage Characteristics .................................................................................. 207
Table 103: Narooma Sewerage System Peak EP Load ............................................................................... 208
Table 104: Design Hydraulic Loadings – Rosedale and Guerilla Bay ........................................................... 211
Table 105: Hydraulic Loading – Bodalla Sewerage Scheme ........................................................................ 212
Table 106: Hydraulic Loading – Bodalla Sewerage Scheme Including Potato Point .................................... 212
Table 107: Sewage Loads – Southern Villages............................................................................................. 212
Table 111: Water Supply Headworks Transfer Capacities ............................................................................ 222
Table 108: Northern WTP Raw Water Quality ............................................................................................... 224
Table 109: Southern WTP Raw Water Quality .............................................................................................. 224
Table 110: Reticulated Water Quality Since 2012 ......................................................................................... 225
Table 112: Incidence of Overflows – Batemans Sewerage System .............................................................. 230
Table 113: Batemans Bay STP – Licence Monitoring Point 3: Treated Effluent ........................................... 230
Table 114: Design Capacity – Batemans Bay STP ....................................................................................... 231
Table 115: Summary of Assessed Capacity of Batemans Bay Secondary Treatment System .................... 232
Table 116: Summary of Conveyance Capacities for Flow Streams – Batemans Bay STP .......................... 232
Table 117: Incidence of Overflows – Tomakin Sewerage System ................................................................ 233
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Table 118: Tomakin STP – Licence Monitoring Point 3: Treated Effluent ..................................................... 234
Table 119: Tomakin STP Assessed Capacities ............................................................................................. 235
Table 120: Incidence of Overflows – Moruya sewerage system .................................................................... 236
Table 121: Moruya STP – Licence Monitoring Point 3: Outlet from Clarifier to Effluent Storage Pond ......... 236
Table 122: Incidence of Overflows – Tuross Sewerage System.................................................................... 238
Table 123: Tuross Head STP – Licence Monitoring Point 3: Treated Effluent .............................................. 239
Table 124: Population and STP Loading Projections ..................................................................................... 239
Table 125: Kianga STP – Licence Monitoring Point 3: Treated Effluent ........................................................ 240
Table 126: Kianga STP Rating Summary ...................................................................................................... 241
Table 127: Batemans Bay STP Recycling Scheme Water Quality Objectives .............................................. 242
Table 128: Batemans Bay STP Recycling Scheme Water Quality Data since 2014 ..................................... 242
Table 129: Moruya STP Recycling Scheme Water Quality Objectives .......................................................... 243
Table 130: Moruya STP Recycling Scheme Water Quality Data ................................................................... 243
Table 131: Bingie STP Recycling Scheme Water Quality Objectives ............................................................ 244
Table 132: Bingie STP Recycling Scheme Water Quality Data since July 2009 ........................................... 244
Table 133: Existing Performance of On-Site Sewerage Systems .................................................................. 246
FIGURES
Figure 1: Eurobodalla Shire Council – IWCM Study Area ................................................................................ 17
Figure 2: Comparison Between Population Growth Forecast from the 2003 IWCMS and Forecast.id Projections (2015) ............................................................................................................................................ 31
Figure 3: Comparison Between Demand Forecast from the 2003 IWCMS, Actual Demand and the Current Forecast Demand ............................................................................................................................................. 32
Figure 4: Annual Volume of Sewage Collected ................................................................................................ 34
Figure 5: Volume of Sewage Treated per Property .......................................................................................... 35
Figure 6: South Durras ..................................................................................................................................... 56
Figure 7: Nelligen ............................................................................................................................................. 56
Figure 8: Long Beach and Maloney’s Beach.................................................................................................... 57
Figure 9: Surfside ............................................................................................................................................. 58
Figure 10: Batemans Bay, Catalina and North Batemans Bay ........................................................................ 59
Figure 11: Surf Beach, Denhams Beach, Sunshine Bay and Batehaven ........................................................ 60
Figure 12: Malua Bay and Lilli Pilli ................................................................................................................... 61
Figure 13: Mogo ............................................................................................................................................... 62
Figure 14: Rosedale and Guerilla Bay ............................................................................................................ 63
Figure 15: Tomakin, Mossy Point and Broulee ................................................................................................ 64
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Figure 16: Moruya Heads ................................................................................................................................ 65
Figure 17: Moruya ............................................................................................................................................ 66
Figure 18: Congo ............................................................................................................................................. 67
Figure 19: Tuross Head ................................................................................................................................... 67
Figure 20: Potato Point .................................................................................................................................... 68
Figure 21: Bodalla ............................................................................................................................................ 68
Figure 22: Narooma, Dalmeny and Kianga ..................................................................................................... 69
Figure 23: Mystery Bay .................................................................................................................................... 70
Figure 24: Central Tilba and Tilba Tilba .......................................................................................................... 70
Figure 25: Akolele ............................................................................................................................................ 71
Figure 26: Water Supply System Schematic ................................................................................................... 72
Figure 27: Eurobodalla Water Supply System ................................................................................................. 73
Figure 28: Clyde River Catchment Map .......................................................................................................... 75
Figure 29: Deua/Moruya River Catchment Map .............................................................................................. 76
Figure 30: Tuross River Catchment Map ......................................................................................................... 77
Figure 31: Conceptual Process Flow Diagram of the Northern Water Supply System ................................... 79
Figure 32: Conceptual Process Flow Diagram of the Southern Water Supply System .................................. 81
Figure 33: Batemans Bay Sewerage System .................................................................................................. 83
Figure 34: Batemans Bay STP Schematic ...................................................................................................... 85
Figure 35: Tomakin Sewerage System ........................................................................................................... 87
Figure 36: Tomakin STP Schematic ................................................................................................................ 89
Figure 37: Moruya Sewerage System ............................................................................................................. 91
Figure 38: Moruya STP Schematic .................................................................................................................. 93
Figure 39: Tuross Head and Turlinjah Sewerage System ............................................................................... 97
Figure 40: Tuross Head (Bingie) STP Schematic ............................................................................................ 98
Figure 41: Narooma Sewerage System ........................................................................................................ 100
Figure 42: Narooma (Kianga) STP Schematic .............................................................................................. 103
Figure 43: Stormwater Sub-Catchment Maps ............................................................................................... 113
Figure 44: Eurobodalla Pricing History .......................................................................................................... 117
Figure 45: Eurobodalla LWU Characteristics – Water Supply Customers .................................................... 118
Figure 46: Eurobodalla LWU Characteristics – Sewerage Customers.......................................................... 131
Figure 47: Total Water Supplied from all Sources – Daily ............................................................................. 138
Figure 48: Total Water Supplied from all Sources – Monthly ........................................................................ 139
Figure 49: Total Water Supplied from all Sources – Annual ......................................................................... 139
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Figure 50: Total Water Supplied from all Sources and Metered Demand – Annual ...................................... 140
Figure 51: Total Water Supplied from all Sources and Shire Population from Census Data ......................... 142
Figure 52: Total Water Supplied from all Sources and Rainfall at Batemans Bay ......................................... 142
Figure 53: Total Water Supplied from all Sources and Restrictions Imposed ................................................ 143
Figure 54: Total Water Supplied from all Sources, Usage Charge (2015$) and Rebates ............................. 143
Figure 55: Peak Demand Period and Daily Rainfall – Summer 2010/11 ....................................................... 144
Figure 56: Peak Demand Period and Daily Rainfall – Summer 2011/12 ....................................................... 145
Figure 57: Peak Demand Period and Daily Rainfall – 2012/13 ...................................................................... 145
Figure 58: Batemans Bay STP Inflow and Rainfall (daily) ............................................................................. 156
Figure 59: Batemans Bay STP Inflow and Rainfall (monthly) ........................................................................ 156
Figure 60: Batemans Bay STP Inflow and Rainfall (annual) .......................................................................... 157
Figure 61: Intensity, Frequency, Duration Analysis of Rainfall – Batemans Bay ........................................... 159
Figure 62: Inflow Variation During Storm Events – Batemans Bay ................................................................ 160
Figure 63: Forecast Biological Loading – Batemans Bay STP ...................................................................... 162
Figure 64: Future Peak and Off-Peak Daily Flow (ADWF) – Batemans Bay STP ......................................... 163
Figure 65: Tomakin STP Inflow and Rainfall (daily) ....................................................................................... 166
Figure 66: Tomakin STP Inflow and Rainfall (monthly) .................................................................................. 166
Figure 67: Tomakin STP Inflow and Rainfall (annual) .................................................................................... 167
Figure 68: Intensity, Frequency, Duration Analysis of Rainfall – Tomakin ..................................................... 169
Figure 69: Inflow Variation During Storm Events - Tomakin .......................................................................... 170
Figure 70: Forecast Tomakin STP Influent Load ........................................................................................... 173
Figure 71: Tomakin STP Forecast Inflow ....................................................................................................... 175
Figure 72: Moruya STP Inflow and Rainfall (Daily): January 1991 – April 2003 ............................................ 179
Figure 73: Moruya STP Inflow and Rainfall (Daily): May 2003 – October 2015 ............................................ 179
Figure 74: Moruya STP Inflow and Rainfall (monthly) .................................................................................... 180
Figure 75: Moruya STP Inflow and Rainfall (annual) ..................................................................................... 180
Figure 76: Intensity, Frequency, Duration Analysis of Rainfall – Moruya ...................................................... 183
Figure 77: Inflow Variation During Storm Events - Moruya ............................................................................ 185
Figure 78: Forecast Moruya STP Influent Load ............................................................................................. 187
Figure 79: Moruya STP Forecast Inflow ......................................................................................................... 188
Figure 80: Tuross Head STP Inflow and Rainfall (daily) ................................................................................ 191
Figure 81: Tuross Head STP Inflow and Rainfall (monthly) ........................................................................... 191
Figure 82: Tuross Head STP Inflow and Rainfall (annual) ............................................................................. 192
Figure 83: Intensity, Frequency, Duration Analysis of Rainfall – Tuross Head .............................................. 195
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Figure 84: Inflow Variation During Storm Events – Tuross Head .................................................................. 196
Figure 85: Forecast Tuross Head STP Influent Load .................................................................................... 198
Figure 86: Bingie STP Forecast Inflow .......................................................................................................... 200
Figure 87: Kianga STP Inflow and Rainfall (Daily) ........................................................................................ 201
Figure 88: Kianga STP Inflow and Rainfall (Monthly) .................................................................................... 202
Figure 89: Kianga STP Inflow and Rainfall (Annual) ..................................................................................... 202
Figure 90: Intensity, Frequency, Duration Analysis of Rainfall – Narooma ................................................... 205
Figure 91: Inflow Variation During Storm Events - Narooma ........................................................................ 206
Figure 92: Forecast Kianga STP Influent Load ............................................................................................. 209
Figure 93: Kianga STP Forecast Inflow ......................................................................................................... 210
Figure 94: Batemans Bay STP Reuse – Overhead Fill ................................................................................. 213
Figure 95: Batemans Bay STP On-site Reuse – Daily .................................................................................. 214
Figure 96: Batemans Bay Golf Course Reuse – Daily .................................................................................. 214
Figure 97: Batemans Bay STP Effluent Reuse – Monthly ............................................................................. 215
Figure 98: Batemans Bay STP Effluent Reuse - Annual ............................................................................... 215
Figure 99: Moruya Golf Course/High School Reuse - Daily .......................................................................... 216
Figure 100: North Moruya Line/Overhead Filler/On-site Reuse - Daily ......................................................... 217
Figure 101: Moruya STP Effluent Reuse – Monthly ...................................................................................... 217
Figure 102: Moruya STP Effluent Reuse - Annual ........................................................................................ 218
Figure 103: Tuross Golf Course Reuse - Daily .............................................................................................. 219
Figure 104: Bingie STP On-site Reuse – Daily ............................................................................................. 219
Figure 105: Bingie STP Effluent Reuse – Monthly ........................................................................................ 220
Figure 106: Bingie STP Effluent Reuse - Annual .......................................................................................... 220
Figure 107: Comparison of Dry Year System Demand, Secure Yield and Licence Entitlement ................... 223
Figure 108: Northern WTP Daily Production and Capacity ........................................................................... 226
Figure 109: Southern WTP Daily Production and Capacity .......................................................................... 226
Figure 110: Total WTP Daily Production and Capacity ................................................................................. 227
Figure 111: Historical and Forecast Peak Day Demand and Treatment Capacity ........................................ 228
Figure 112: Forecast ADWF and Design Capacity – Tomakin STP.............................................................. 234
Figure 113: Forecast ADWF, PDWF and Design Capacity – Moruya STP ................................................... 237
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PART A: IWCM ISSUES
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1. DOCUMENT STRUCTURE
Part A of this document provides the information required for the IWCM Issues Paper (Item 8) as listed in the Integrated Water Cycle Management Strategy Check List – July 2014 (NSW Office of Water, 2014).
Table 1: IWCM Issues Paper – Check List Requirements
Outcome Achieved Section in this Document
8A. Summary of all the outcomes from items 2 to 7. Section 2. The Background Information (items 2 to 7) is provided in Part B
8B. A summary table of the information and data gaps relating to regulatory compliance and Levels of Service (LOS) targets based on a review of all the reference documents and operational monitoring data.
Sections 3
8C. A table capturing all (existing unresolved, new and emerging) issues in each water service system that have been identified through the analysis, site inspection and from community consultation, and clearly showing whether the issue is one of regulatory compliance, LOS or capacity.
Section 4
8D. Known recurrent and non-recurrent issues from a review of maintenance logs, incident reports, annual Action Plan and TBL Reports, customer complaints, EPA Public register licence breaches and NOW system inspections (section 61 of Local Government Act 1993).
8E. All items requiring a capital works resolution.
8F. Includes a brief review to identify issues to support your city, town or village water-sensitive urban design (WSUD) and the broader ‘liveable towns and cities’ objectives as per paragraph 92 of the National Water Initiative.
Section 5
8G. Includes a summary of the existing Total Asset Management Plan (TAMP) measures and their current status. Check whether any of the identified issues are being addressed through the measures in the TAMP that are at an advanced stage of implementation.
Section 6
8H. Includes item 6.7 on page 10 of the SBP Check List relating to your Drinking Water Management System.
Section 7
A ‘value for money’ review of the appropriateness and effectiveness of the existing TAMP of your LWU’s existing SBP in addressing all of the outstanding issues, for example:
8I. The current program measures in the non-build water conservation and inflow/infiltration measures need to be reviewed based on current performance data, new knowledge and technology, regulation, community acceptance, possible new integration, etc.
8J. The capital works program review to consider whether the issues (existing, new or emerging) could be more cost-effectively addressed using an alternative solution path.
Section 5
8K. Provide Issues Paper to NSW Office of Water for review and concurrence. To be provided.
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2. SUMMARY OF BACKGROUND INFORMATION
Part B of this document provides the available data in response to the IWCM Checklist items.
The majority of towns and villages in Eurobodalla Shire are supplied with water through the regional water supply scheme which consists of two sub systems (northern system and southern system). The water supply system stretches from Maloney’s Beach in the north to Mystery Bay 90 km to the south and services approximately 20,000 properties including the main population centres of Batemans Bay, Moruya and Narooma. The northern area supplies from Maloney’s Beach to Tuross Head and the southern area supplies from Bodalla to Central Tilba and Mystery Bay. These areas are interconnected and each can feed the other area if required.
The northern system draws water from the Deua/Moruya and Buckenboura Rivers which feed into an off river storage (Deep Creek Dam). The main components of the northern system includes a WTP at Denham’s Beach with a capacity of 20 ML/d, 22 service reservoirs with a total capacity of 88 ML, 8 pumping stations and 535 km of distribution/reticulation mains.
The southern system draws water from the Tuross River/Tuross alluvial aquifer which feeds directly to the southern WTP (i.e. no storage). The southern system consists of a WTP on the Tuross River west of Bodalla (6 ML/d), 11 service reservoirs (26.7 ML), 3 pumping stations and 210 km of distribution/reticulation mains.
There are five sewerage schemes serving the majority of towns and villages. All the STPs consist of relatively similar process configurations that generally include primary treatment (screening and grit removal), secondary treatment (activated sludge and clarification processes) and tertiary treatment (maturation ponds, UV disinfection and/or chlorination for reuse streams). Current effluent management practices are as follows:
· Batemans Bay STP – Ocean outfall and reuse at Catalina Golf Course and at Hanging Rock Sporting Fields (8% on average);
· Tomakin STP – Ocean outfall;
· Moruya STP – Release to Ryans Creek which flows to the Moruya River. Reuse at Moruya Golf Course, Moruya High School and Riverside Park (25% on average);
· Tuross STP – Dune exfiltration with reuse at Tuross Golf Course (9% on average); and
· Narooma STP – Ocean outfall.
In recent times, Eurobodalla Shire Council (ESC) has undertaken significant strategic planning to identify current and future water supply and sewerage asset requirements including:
· Analysis of secure yield of the water supply headworks system (NSW Public Works, 2013a);
· Forecast water supply demand (NSW Public Works, 2014a);
· Hydraulic modelling of the water supply network (NSW Public Works, 2014b);
· Off-stream storage options investigations and detailed design of southern off-stream storage (in progress);
· Drinking Water Management System (NSW Public Works and Atom Consulting, 2014);
· Optimisation of Southern WTP (NSW Public Works, 2014h);
· Forecast sewerage system demand (NSW Public Works, 2014a);
· Hydraulic modelling of the sewerage systems - Moruya (NSW Public Works, 2014d), Tuross (NSW Public Works, 2014e), Tomakin (NSW Public Works, 2014f) and Batemans Bay (NSW Public Works, 2016). Modelling of the Narooma system is in progress;
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· Analysis of capacity of Narooma STP (ASpect Process Services, 2015), Tomakin STP (NSW Public Works, 2012), Tuross STP (NSW Public Works (2014g, 2015a)) and Batemans Bay STP (NSW Public Works (2015b);
· Options for transfer of Batemans Bay southern catchment sewerage to Tomakin STP (Malua Bay Diversion);
· STP upgrade concept development – Tomakin (NSW Public Works, 2012 and 2013b) and Batemans Bay (NSW Public Works (2015b);
· Options for additional effluent reuse (NSW Public Works (2014c); and
· Design of Bodalla/Potato Point and Rosedale/Guerilla Bay sewerage schemes (in progress).
These documents together with water supply and sewerage operational data have been used to address the IWCM checklist components and identify the IWCM Issues.
3. COMPLIANCE WITH OPERATING ENVIRONMENT REQUIREMENTS
During the development of this IWCM Issues Paper, data from Council, stakeholders and publicly available information were reviewed. A summary of the available information relating to regulatory compliance and LOS targets is given in the following table.
Table 2: Operating Environment Compliance Summary
Requirement Compliance Summary
Legislative Requirements ESC complies with all legislative and contractual requirements related to IWCM.
Australian Guidelines for Water Recycling (2006)
The Australian Guidelines for Water Recycling: Managing Health and Environmental Risks (2006) require that a risk management approach is applied to management of effluent reuse schemes. The existing management plans for Moruya Golf Course and High School and Tuross Head Country Club recycling schemes were prepared following previous guidelines and should be reviewed and updated.
Council complies with all other guidelines, standards and codes relevant to IWCM.
Australian Drinking Water Guidelines (ADWG, 2011)
ESC has prepared a Drinking Water Management System (DWMS) in accordance with the ADWG. The NSW Health and DPI-Office of Water Guidelines require an annual review of the DWMS which has not yet been undertaken. An external audit is also required.
Water Extraction Licences ESC complies with the town water access licences issued under the Water Act, 1912.
Environment Protection Licences
ESC generally complies with the Environment Protection Licences issued for the five sewerage schemes. Recent non-compliances are related to high inflow and infiltration into the Tuross and Batemans Bay sewerage systems.
Levels of Service ESC generally complies with the target levels of service. Sewerage system modelling predicts the occurrence of sewerage system overflows during the 1 in 5 year and 1 in 20 year rainfall events. Water supply system modelling has identified the need for treatment plant, trunk system and reticulation network upgrades to cater for future demand.
The information gained from the data review was generally adequate to identify current issues, however, addressing the data gaps listed in the following table would improve the understanding of the issues facing ESC in urban water service delivery both now and into the future.
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Table 3: Data Gaps
No. Data Gap Related Obligation/Target Actions
D1 Asset condition Best Practice Management of Water Supply and Sewerage Guidelines
While inspection programs such as CCTV are in place to assess the condition of some assets with results used to identify priority renewal projects, there is no register of asset condition. Documented asset condition and adjusted remaining life would assist with development of maintenance and renewal programs.
D2 Hydraulic modelling of the Narooma sewerage system
Levels of service Modelling of the Narooma system has commenced. Calibration of flows is required to predict overflow locations.
D3 Hydraulic modelling of the Batemans Bay sewerage system
Levels of service Modelling of the Batemans Bay system has commenced. Calibration of flows is required to predict overflow locations.
4. IWCM ISSUES
IWCM issues that have been identified from the background information are given in the following table. Capital works and operating budgets are discussed in Section 5.
Table 4: IWCM Issues
Issue Type of Issue Status of Issue and Proposed Solution
Water Supply
I1 Based on the secure yield estimate for the existing water supply headworks system, the existing supply is expected to be sufficient to meet demand until 2020. If the WSP is gazetted with the extraction rules modelled in the secure yield study, the water supply sources will not be sufficient to supply the dry year demand during a repeat of the worst drought. The secure yield of the water supply system is partly constrained by the capacity of the WTPs.
Capacity, LOS Solution has been identified and included in budgets.
Council is now proceeding with completion of detailed design and the purchasing of land for the southern off stream storage during 2016/17 and 2017/18. This will ensure the project is well developed and Council is in a strong position should appropriate funding opportunities arise.
The capital works program includes $12,000k in 2036 to upgrade and augment the Northern WTP and $20,000k from 2032 to construct a new Southern WTP at the new dam site. The timing of the WTP upgrades has not been determined but will consider the secure yield and PDD requirements.
Additional yield modelling will be undertaken to assess the secure yield of the augmented system including additional storage and treatment plant upgrades.
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Issue Type of Issue Status of Issue and Proposed Solution
I2 The reticulated water quality does not always meet guideline values. The pH of the reticulated water was above the guideline value on many occasions which may cause corrosion of pipes and fittings, the level of fluoride has been lower than the concentration required for effective dental caries prevention for the majority of the time and the free chlorine in the distribution system in often below the level required for effective disinfection.
LOS Existing unresolved issue.
The DWMS identified a list of actions to improve treatment plant performance which have partly been implemented. ESC will conduct a review and audit of the DWMS in 2016/17 to assess the current treatment plant effectiveness and identify any remedial actions.
I3 Water supply network modelling has identified deficiencies in the trunk water supply and reticulation system.
Capacity, LOS Solution has been identified and included in budgets.
The water network modelling has identified the required system upgrades and reticulation system upgrades to meet minimum pressure at peak instantaneous demand for 2046 demand. These upgrades will be addressed as part of the water supply renewal program.
Batemans Bay Sewerage
I4 Batemans Bay experiences a high proportion of holiday visitors over the summer season and the STP experiences a clear peak and off peak load. The Batemans Bay STP has insufficient capacity to treat current peak season loads.
Capacity, LOS Solution has been identified and included in budgets.
ESC plans to divert flows from the Malua Bay and Lilli Pilli sewer catchments to the Tomakin STP to reduce the demand on the Batemans Bay STP. The Malua Bay diversion is planned to be constructed in 2021.
I5 The recycled water to the Catalina Country Club exceeded the water quality guidelines for BOD, suspended solids and E. coli on a few occasions.
Regulatory compliance
Existing unresolved issue.
The Operational Environmental Management Plan includes procedures to cease supply when water quality is inadequate. A Recycled Water Management System will be developed in accordance with current guidelines.
I6 High inflow and infiltration into the Batemans Bay sewerage system affects the ability of the Batemans Bay STP to achieve licence conditions for effluent quality and load.
Regulatory compliance
Solution has been identified and included in budgets.
The existing operations and maintenance budget includes $1,000k p.a. for sewer main replacement, relining and junction sealing across the shire. Priority areas are identified through CCTV inspection and smoke testing programs.
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Issue Type of Issue Status of Issue and Proposed Solution
I7 Sewer network modelling predicts overflows from the Batemans Bay sewerage system during the 1 in 5 year 1 hour rainfall event and 1 in 20 year rainfall event.
Capacity, LOS Solution has been identified.
The network modelling report has identified the upgrades required to avoid overflows during the 1 in 5 year 1 hour rainfall event. Sewer relining will also be required. The timing of these upgrades is yet to be confirmed. The existing operations and maintenance budget includes $1,000k p.a. for sewer main replacement, relining and junction sealing across the Shire. Priority areas are identified through CCTV inspection.
Tomakin Sewerage
I8 Tomakin experiences a high proportion of holiday visitors over the summer season and the STP experiences a clear peak and off peak load. The Tomakin STP has insufficient capacity to treat current peak season loads.
Capacity, LOS Solution has been identified and included in budgets.
Minor capital upgrades and operational adjustments will be made to allow for appropriate peak period treatment.
I9 Sewer network modelling predicts overflows from the Tomakin sewerage system during the 1 in 5 year 1 hour rainfall event and 1 in 20 year rainfall event.
Capacity, LOS Solution has been identified.
The network modelling report has identified the upgrades required to avoid overflows during the 1 in 5 year 1 hour rainfall event. With a relined system, modelling predicts there will be no overflows and upgrades would not be required. The existing operations and maintenance budget includes $1,000k p.a. for sewer main replacement, relining and junction sealing across the Shire. Priority areas are identified through CCTV inspection.
Moruya Sewerage
I10 Sewer network modelling predicts overflows from the Moruya sewerage system during the 1 in 5 year 1 hour rainfall event and 1 in 20 year rainfall event.
Capacity, LOS Solution has been identified.
The network modelling report has identified the upgrades required to avoid overflows during the 1 in 5 year 1 hour rainfall event and 1 in 20 year rainfall event. The timing of these upgrades is yet to be confirmed.
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Issue Type of Issue Status of Issue and Proposed Solution
Tuross Sewerage
I11 High inflow and infiltration into the Tuross sewerage system affects the ability of the Bingie STP to achieve licence conditions for effluent quality.
Regulatory compliance
Solution has been identified and included in budgets.
The existing operations and maintenance budget includes $1,000k p.a. for sewer main replacement, relining and junction sealing across the shire. Priority areas are identified through CCTV inspection.
I12 Tuross Head experiences a high proportion of holiday visitors over the summer season and the STP experiences a clear peak and off peak load. The Bingie STP has insufficient capacity to treat current peak season loads.
Capacity, LOS Solution has been identified and included in budgets.
Minor capital upgrades and operational adjustments will be made to allow for appropriate peak period treatment.
I13 The recycled water supplied to the Tuross golf course exceeded the water quality guidelines and targets for pH, suspended solids and faecal coliforms on a number of occasions.
Regulatory compliance
Existing unresolved issue.
The Operational Environmental Management Plan includes procedures to cease supply when water quality is inadequate. A Recycled Water Management System will be developed in accordance with current guidelines.
I14 Sewer network modelling predicts overflows from the Tuross sewerage system during the 1 in 5 year 1 hour rainfall event and 1 in 20 year rainfall event.
Capacity, LOS Solution has been identified.
The network modelling report has identified the upgrades required to avoid overflows during the 1 in 5 year 1 hour rainfall event. The timing of these upgrades is yet to be confirmed.
Narooma Sewerage
I15 The Kianga STP has insufficient capacity to treat current peak season loads.
Capacity, LOS Solution has been identified and included in budgets.
Operational, minor and major capital upgrades have been identified for the Kianga STP. The capital budget includes and allowance of $5,000k in 2021 for these works.
I16 Sewer network modelling predicts overflows from the Narooma sewerage system during the 1 in 5 year 1 hour rainfall event and 1 in 20 year rainfall event.
Capacity, LOS Solution has been identified.
The network modelling report has identified the upgrades required to avoid overflows during the 1 in 5 year 1 hour rainfall event. The timing of these upgrades is yet to be confirmed.
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Issue Type of Issue Status of Issue and Proposed Solution
Unserviced Areas
I17 Due to the sandy nature of the soil it is commonly acknowledged that sewage/effluent from on-site wastewater management systems in South Durras will infiltrate the groundwater aquifer and ultimately end up in the waterways (Durras Lake). Groundwater quality results (sampled in the mid-1980s) show elevated nitrate levels and the presence of faecal bacteria confirming the contamination of the groundwater from poorly managed on-site wastewater management systems.
LOS Existing unresolved issue.
ESC consulted with Durras residents regarding the OSSM program during 2013.
Based on community feedback, the NSW EPA has requested that ESC consider a long-term (25-30 year) plan for local treatment and re-use of effluent (recycled water and biosolids) and no ocean outfall disposal. Provision of reticulated water would be necessary and required at the same time (refer I16).
I18 Council inspections in South Durras have identified over 40 unlicensed bores/spearpoints which are close to septic absorption trenches. Due to the Category 1 soils (sand) and shallow groundwater there is a high risk of contamination of the groundwater supplies. Whilst some properties only use this water for garden/toilet flushing purposes, the absence of large water tanks on some properties indicates that bore water may also be used for showering and potable use. Even if used only for gardening/toilet flushing there is still the risk of contamination of food crops or inhalation of aerosols.
Regulatory compliance
To be addressed by DPI-Water as part of water extraction licensing.
I19 The village of Nelligen drains into priority oyster aquaculture areas of the Clyde River. Water quality is a key concern for the oyster industry. Re-development of properties within Nelligen has resulted in limited space for on-site systems.
LOS Existing unresolved issue.
ESC plans to investigate options for provision of water supply and sewerage services to Nelligen in the near future.
I20 Site inspections have revealed approximately 50% of septic systems in Rosedale and Guerilla Bay are not satisfactory due to small lot sizes, high peak loads, poor soil permeability, clogging of the trenches and odours. These problems result in social and environmental impacts and significant potential public health risks.
LOS Solution has been identified and included in budgets.
The Rosedale and Guerilla Bay Sewerage Scheme will be constructed by 2017.
I21 The existing on-site septic tank and effluent disposal systems in Bodalla are prone to failure due to hydraulic overloading, unsuitable lot sizes and poor ground conditions for effluent disposal. Apart from visual impacts and public health concerns, it is probable that these problems are having an impact on local water quality, including surface waterways and groundwater systems.
LOS Solution has been identified and included in budgets.
The Bodalla Sewerage Scheme (pressure sewerage) will be constructed by 2018.
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Issue Type of Issue Status of Issue and Proposed Solution
I22 The existing wastewater management systems in Mystery Bay are unsatisfactory due to hydraulic overloading and poor ground conditions for effluent disposal.
LOS Existing unresolved issue.
Mystery Bay has a centralised water supply. ESC will progress the investigation of sewerage schemes for the southern villages from 2023. Construction of the schemes will depend on funding and community consultation.
I23 The existing wastewater management systems in Central Tilba and Tilba Tilba are unsatisfactory due to hydraulic overloading, unsuitable lot sizes, poor ground conditions for effluent disposal and disruptions and odours during pump out.
LOS Existing unresolved issue.
Central Tilba and Tilba Tilba have a centralised water supply. ESC will progress the investigation of sewerage schemes for the southern villages from 2023. Construction of the schemes will depend on funding and community consultation.
I24 The existing wastewater management systems in Akolele are unsatisfactory due to overflows from on-site systems to sensitive water bodies including oyster lease areas.
LOS Existing unresolved issue.
Akolele has a centralised water supply. ESC will progress the investigation of sewerage schemes for the southern villages from 2023. Construction of the schemes will depend on funding and community consultation.
The NSW Office of Water has constructed a sewerage scheme servicing Koori Village/Wallaga Lake. This scheme allows for future servicing of Akolele.
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5. WATER SENSITIVE URBAN DESIGN OBJECTIVES
Council’s Infrastructure Design Standards (IDS) details the requirements for the design of infrastructure undertaken on Council, Crown or private land within Eurobodalla Shire. Chapter 11 of the IDS covers stormwater treatment and applies consistent best practice WSUD measures and principles. Related objectives are:
· To ensure treatment methods and associated structures are cost effective from a maintenance and operational perspective and that the risk to the public is minimised as far as practicable;
· To protect and enhance natural water systems within urban environments;
· To integrate stormwater treatment into the landscape, maximising the visual and recreational amenity of developments; and
· To improve the quality of water draining from urban developments into receiving environments.
6. TOTAL ASSET MANAGEMENT PLAN STATUS AND REVIEW
ESC has developed a 30 year capital works program and operational budget. A summary of the main budget components is included in the following tables. Renewal budgets have been adopted for all assets. Major STP renewals are included in the budgets for STP augmentations. Many of the IWCM issues (refer Table 4) are being addressed through existing TAMP measures.
Table 5: Water Supply Capital Works Budget
Component Budget (2017$)
Comments
Renewals
Water meter $260k p.a. Water meters replaced at 10 years, at 5,000 kilolitres or when failed.
Services $60k p.a. Allocation for replacement of water services not replaced when the main is replaced.
Valves and hydrants $140k p.a. Valves and hydrants have a design life of approximately half the design life of the water main. Allocation for replacement of valves/hydrants at mid-life of the water main.
Mains $1,500k p.a. Allocation for replacement of water mains at approximately 1.0% of the network annually from 2017/18. Increase to 1.25% from 2040 with an additional construction crew.
Telemetry and SCADA $45k p.a. Allowance
Pumping stations $120k p.a. Refurbishment or replacement of water pumping stations, including pump refurbishments and replacements.
Augmentation
Northern WTP $12,000k Planned to commence 2035/36.
New Assets
New Service Connections $140k p.a. New 20mm & 25mm water service connections
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Component Budget (2017$)
Comments
Southern Dam $64,000k New 3,000 ML dam near Bodalla, including river pumping station and transfer mains. Design to commence 2016/17, construction planned to commence 2019/20 depending on funding.
New Southern WTP $20,000k New 10 (+5) ML/day WTP at the new dam site, including decommissioning the existing plant.
Pressure reduction $200k p.a. 2017/18 and 2018/19
Table 6: Water Supply Operation and Maintenance Budget
Component Budget (2017$)
Comments
Dams and weirs $100k p.a. Increasing to $200k p.a. from 2024 once new dam is operational.
Groundwater $90k p.a.
Mains $1,000k p.a. Increasing to $1,100k p.a. from 2024 and $1,200k p.a. from 2032
Pumping stations $700k p.a. Increasing to $900k p.a. from 2024.
Reservoirs $130k p.a.
Telemetry $170k p.a.
Trunk mains $200k p.a.
Treatment and disinfection $790k p.a. Increasing to $1,000k p.a. from 2035 with new Southern WTP.
Meters $650k p.a. Increasing to $700k p.a. from 2022, $750k p.a. from 2028, $800k p.a. from 2034 and $850k p.a. from 2040
Water quality management $170k p.a.
Demand education $105k p.a. Environment Education Officer 2xFTE. Advertising, bill Inserts and miscellaneous education supplies.
Water savings incentives program
$50k p.a. Washing Machine, Toilet Cistern, Rainwater Tank and Auto Leak Shutoff rebates.
Water loss management $30k p.a. Leak detection, water balance reporting, etc.
Non-residential water savings program
$25k p.a. Water Audit Consultant fees (5 businesses audited p.a.), Data logger fees and mobile data usage charges.
Reservoir condition assessment $25k p.a. Contract divers carry out reservoir cleaning and prepare condition assessment reports. Inspection of steel reservoirs by contract paint technologist to assess protective coating condition. Rolling 5 year program.
Table 7: Sewerage Capital Works Budget
Component Budget (2017$)
Comments
Renewals
Mains $1,000k p.a. Allocation for the replacement of sewer mains and service connections, including relining sewers and sealing junctions.
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Component Budget (2017$)
Comments
Manholes $200k p.a. Allocation for the refurbishment or replacement of sewer access chambers.
Pumping stations $1,500k p.a.
STPs minor renewals $250k p.a.
SCADA and telemetry $50k p.a.
Batemans Bay STP sludge management
$500k Centrifuge renewal
Augmentation
Batemans Bay STP $5,500k Scheduled 25 year mechanical and electrical upgrade. Design to be completed 2017. Construction 2018
Bodalla STP $1,200k Upgrade planned to commence 2021 to accommodate Potato Point.
Bingie STP $1,150k Stage 1 capacity upgrade 2017/18 - aeration and chemical dosing plus electrical and mechanical upgrade. Stage 2 capacity upgrade 2026. New STP at 60 years in 2044.
Tomakin STP $22,400k Major upgrade to commence 2020.
Kianga STP $5,300k Scheduled 25 year mechanical and electrical upgrade. To commence 2019.
Moruya STP $1,100k Scheduled 25 year mechanical and electrical upgrade. To commence 2021.
New Assets
New Service Connections $20k p.a. New sewer junctions in existing sewers
Bodalla sewerage $7,800k New sewerage scheme servicing the village of Bodalla. Includes the construction of low pressure sewerage, STP and irrigation scheme. Commencing 2016/17.
Rosedale and Guerilla Bay sewerage
$7,000k New sewerage scheme servicing the villages of Rosedale and Guerilla Bay, commenced 2015/16.
Potato Point sewerage $6,000k New sewerage scheme servicing the village of Potato Point. To connect to Bodalla STP, commencing 2021.
Malua Bay Diversion $8,000 Divert flows from the Malua Bay and Lilli Pilli sewer catchments to the Tomakin STP to reduce the demand on the Batemans Bay STP in 20/21.
Table 8: Sewerage Operation and Maintenance Budget
Component Budget (2017$)
Comments
Mains $2,000k p.a.
Pumping stations $1,700k p.a.
Telemetry $180k p.a.
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Component Budget (2017$)
Comments
Odour treatment $150k p.a.
CCTV condition assessment $150k p.a. - $270k p.a.
Budget based on assessing 5% of sewers aged 0-40 years, 10% of sewers 40-80 years, and 20% of sewers 80+ years (budget is increasing as the asset ages).
The adopted budget includes $155k p.a. for residential demand management (education and rebates), $25k p.a. for non-residential water savings and $30k p.a. for water loss management. This is an appropriate level of expenditure which balances the low residential demand per property (119 kL/a in 2013/14) and low level of water losses (12% non-revenue water or approximately 60 L/connection/day) with the need to augment the water supply in the near future to increase the secure yield.
ESC has undertaken extensive strategic planning to address the IWCM issues. While these solutions will be developed and optimised, the overall solutions are considered to be appropriate.
7. DRINKING WATER MANAGEMENT SYSTEM STATUS
The ESC Drinking Water Management System (DWMS, NSW Public Works and Atom Consulting, 2014) and the supporting systems address the requirements of the Public Health Act 2010 (NSW) and the twelve elements of the “Framework for Drinking Water Quality Management” provided in the Australian Drinking Water Guidelines (ADWG). The DWMS acts as a roadmap of the activities that Council undertakes to ensure the provision of safe drinking water to its customers.
An Improvement Plan has been developed as part of the DWMS to demonstrate how Council will address the risks identified through the DWMS or to improve compliance with the ADWG. The Plan prioritises resources on high risks, ensuring the safest possible drinking water.
A review of the DWMS has not yet been undertaken.
8. CONSULTATION Council continues to liaise with regulatory agencies (NSW EPA, DPI-Water, etc.) regarding sewerage system licence compliance, best-practice water supply and sewerage management and development of water sharing plans. Council has also consulted with the communities of Rosedale/Guerilla Bay, Bodalla and South Durras regarding the need for improved wastewater management. In 2010, ESC conducted a suite of community engagement activities to inform the development of the Eurobodalla Community Strategic Plan (eurobodalla2030). The outcomes of these consultation activities have been incorporated in this IWCM Issues Paper.
The Integrated Water Cycle Management Strategy Check List includes the requirement for consultation with stakeholders during the development of the IWCM Strategy. A Project Reference Group (PRG) will be formed to:
· Provide input on all existing and potential issues that affect the community relating to provision of the urban water service over the next 30 years;
· Help identify suitable options for managing these issues; and
· Help review and confirm the proposed IWCM Strategy.
Apart from the adequacy of village water and sewerage schemes, the IWCM issues identified in this document are not directly relevant to individual customers or groups. In addition, the proposed solutions to the identified issues are not expected to be significantly different to the current strategy (adopted from the 2003 IWCM Strategy) and Council has not identified any community groups that would be relevant to the current IWCM Strategy development.
EUROBODALLA SHIRE COUNCIL – IWCM ISSUES PAPER
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For the purposes of development of this IWCM Strategy, ESC will form a PRG for the development of the IWCM Strategy including agency representatives, Council staff and Councillors who are considered to be appropriate representatives of the community. The IWCM Issues and potential options to address them will be presented to the PRG for review.