California Water Service 2015 Urban Water Management Plan City of Hawthorne District June 2016 Quality. Service. Value 2015 Urban Water Management Plan California Water Service City of Hawthorne District Table of Contents List of Tables ................................................................................................................................... 5 List of Figures .................................................................................................................................. 8 List of Acronyms .............................................................................................................................. 9 Chapter 1 Introduction and Overview .......................................................................................... 11 1.1 Background and Purpose ............................................................................................... 11 1.2 Urban Water Management Planning and the California Water Code ........................... 12 1.3 Relation to Other Planning Efforts ................................................................................. 13 1.4 Plan Organization ........................................................................................................... 13 Chapter 2 Plan Preparation ........................................................................................................... 15 2.1 Basis for Preparing a Plan ............................................................................................... 15 2.2 Regional Planning ........................................................................................................... 16 2.3 Individual or Regional Planning and Compliance ........................................................... 16 2.4 Fiscal or Calendar Year and Units of Measure ............................................................... 17 2.5 Coordination and Outreach ........................................................................................... 17 2.5.1 Wholesale and Retail Coordination ........................................................................ 17 2.5.2 Coordination with Other Agencies and the Community ........................................ 18 Chapter 3 System Description ...................................................................................................... 19 3.1 Service Area General Description .................................................................................. 19 3.2 Service Area Maps .......................................................................................................... 20 3.3 Service Area Climate ...................................................................................................... 21 3.3.1 Climate Change ....................................................................................................... 23 3.4 Service Area Population and Demographics .................................................................. 25 Chapter 4 System Water Use ........................................................................................................ 27 4.1 Recycled versus Potable and Raw Water Demand ........................................................ 27 4.2 Water Uses by Sector ..................................................................................................... 27 4.2.1 Historical Potable and Raw Water Uses ................................................................. 27 4.2.2 Projected Potable and Raw Water Uses ................................................................. 30 4.2.3 Total Water Demand Including Recycled Water .................................................... 32 4.3 Distribution System Water Losses ................................................................................. 32 Printed 4/28/2017 Page 1 2015 Urban Water Management Plan California Water Service City of Hawthorne District 4.4 Estimating Future Water Savings ................................................................................... 33 4.5 Water Use for Lower Income Households ..................................................................... 36 4.6 Climate Change .............................................................................................................. 37 Chapter 5 Baselines and Targets ................................................................................................... 39 5.1 Wholesale Agencies ....................................................................................................... 40 5.2 Updating Calculations from 2010 UWMP ...................................................................... 40 5.3 Baseline Periods ............................................................................................................. 40 5.3.1 Determination of the 10-15 Year Baseline Period .................................................. 41 5.3.2 Determination of the 5-Year Baseline .................................................................... 41 5.4 Service Area Population ................................................................................................. 41 5.5 Gross Water Use ............................................................................................................. 43 5.6 Baseline Daily Per Capita Water Use .............................................................................. 45 5.7 2015 and 2020 Targets ................................................................................................... 45 5.8 2015 Compliance Daily per Capita Water Use ............................................................... 46 5.9 Regional Alliance ............................................................................................................ 47 Chapter 6 System Supplies............................................................................................................ 49 6.1 Purchased Water ............................................................................................................ 50 6.2 Groundwater .................................................................................................................. 50 6.2.1 Basin Description .................................................................................................... 50 6.2.2 Groundwater Management .................................................................................... 51 6.2.3 Overdraft Conditions .............................................................................................. 55 6.2.4 Historical Pumping .................................................................................................. 56 6.3 Surface Water ................................................................................................................. 56 6.4 Stormwater .................................................................................................................... 56 6.5 Wastewater and Recycled Water ................................................................................... 57 6.5.1 Recycled Water Coordination ................................................................................. 57 6.5.2 Wastewater Collection, Treatment, and Disposal .................................................. 57 6.5.3 Recycled Water System .......................................................................................... 62 6.5.4 Recycled Water Beneficial Uses .............................................................................. 62 6.5.5 Actions to Encourage and Optimize Future Recycled Water Use .......................... 64 6.6 Desalinated Water Opportunities .................................................................................. 65 Printed 4/28/2017 Page 2 2015 Urban Water Management Plan California Water Service City of Hawthorne District 6.7 Exchanges or Transfers .................................................................................................. 65 6.7.1 Exchanges ................................................................................................................ 65 6.7.2 Transfers ................................................................................................................. 66 6.7.3 Emergency Interties ................................................................................................ 66 6.8 Future Water Projects .................................................................................................... 66 6.9 Summary of Existing and Planned Sources of Water ..................................................... 68 6.10 Climate Change Impacts to Supply ............................................................................. 70 6.10.1 Estimating Changes in Climate ................................................................................ 70 6.10.2 Impacts of Climate Change on Water Supplies ...................................................... 71 6.10.3 Next Steps and Key Conclusions ............................................................................. 72 Chapter 7 Water Supply Reliability Assessment ........................................................................... 75 7.1 Constraints on Water Sources........................................................................................ 75 7.2 Reliability by Type of Year .............................................................................................. 76 7.3 Supply and Demand Assessment ..................................................................................