2020 Facilities Plan June 2020 Final Table of Contents Executive Summary ......................................................................................................... ES-1 ES.1 Study Area ............................................................................................................................................................... ES-1 ES.2 Land Use and Population Projections .......................................................................................................... ES-1 ES.3 Water Supply .......................................................................................................................................................... ES-1 ES.4 Water Demand....................................................................................................................................................... ES-2 ES.5 Treated Water Storage ....................................................................................................................................... ES-2 ES.6 Fire Protection ....................................................................................................................................................... ES-2 ES.7 Distribution System............................................................................................................................................. ES-3 ES.8 Facilities Planning ................................................................................................................................................ ES-3 Section 1 Introduction ....................................................................................................... 1-1 1.1 Background ................................................................................................................................................................. 1-1 1.2 Report Organization ................................................................................................................................................ 1-1 1.3 Acknowledgments .................................................................................................................................................... 1-2 Section 2 Study Area Characteristics .................................................................................. 2-1 2.1 Location ........................................................................................................................................................................ 2-1 2.2 Climate ........................................................................................................................................................................... 2-1 2.3 Topography ................................................................................................................................................................. 2-2 2.4 Soils ............................................................................................................................................................................. 2-2 Section 3 Development of the Study Area ......................................................................... 3-1 3.1 Historical Perspective ............................................................................................................................................. 3-1 3.2 Land Use Planning Information .......................................................................................................................... 3-1 3.3 Existing Land Use ...................................................................................................................................................... 3-2 3.4 Buildout Land Use .................................................................................................................................................... 3-3 3.5 Dwelling Units ............................................................................................................................................................ 3-4 3.6 Population Growth ................................................................................................................................................... 3-5 Section 4 Existing Water System ........................................................................................ 4-1 4.1 Water Supply and Treatment .............................................................................................................................. 4-1 4.1.1 Surface Water Supply ................................................................................................................................ 4-1 4.1.2 Randall-Bold WTP ....................................................................................................................................... 4-2 4.1.3 Groundwater Supply .................................................................................................................................. 4-3 4.2 Corporation Yard ...................................................................................................................................................... 4-8 4.3 DWD Distribution System ..................................................................................................................................... 4-9 4.4 Interties .......................................................................................................................................................................4- 10 4.5 Other Water Systems within DWD’s Planning Area ................................................................................4-10 4.6 Future Opportunities ............................................................................................................................................4- 12 Section 5 Water Demand ................................................................................................... 5-1 5.1 Historical and Projected Customer Connections ........................................................................................ 5-1 5.2 Historical Water Use by DWD Customers ...................................................................................................... 5-3 5.3 Unit Demand Factors ............................................................................................................................................... 5-4 5.4 Peaking Factors and Diurnal Curve .................................................................................................................. 5-5 i Table of Contents 5.5 Water Demand Projections ................................................................................................................................... 5-8 Section 6 Treated Water Storage ....................................................................................... 6-1 6.1 Existing Storage Facilities ..................................................................................................................................... 6-1 6.2 Criteria for Storage Volume .................................................................................................................................. 6-1 6.3 Treated Water Storage Requirements ............................................................................................................. 6-2 6.4 Ultimate Storage Facilities .................................................................................................................................... 6-3 Section 7 Fire Protection ................................................................................................... 7-1 7.1 Fire Protection Agency ........................................................................................................................................... 7-1 7.2 ISO Rating ..................................................................................................................................................................... 7-1 7.3 Fire Protection Objectives ..................................................................................................................................... 7-2 7.4 Available Fire Flow – Existing and Future...................................................................................................... 7-4 Section 8 Distribution System Network ............................................................................. 8-1 8.1 Hydraulic Model Description ............................................................................................................................... 8-1 8.1.1 Model History ................................................................................................................................................ 8-1 8.1.2 Model Updates for Facilities Plan ......................................................................................................... 8-1 8.1.3 Updated Demand Allocations ................................................................................................................. 8-2 8.1.4 Model Calibration and Verification ...................................................................................................... 8-2 8.2 Analysis Criteria ........................................................................................................................................................ 8-2 8.2.1 Pressures ........................................................................................................................................................