Chapter 8 Drainage & Wastewater Infrastructure Chapter 8 Drainage and Wastewater Infrastructure .................................. 8-1 8.1 Key Terms ...................................................................................................................... 8-2 8.1.1 Abbreviations .................................................................................................................................... 8-2 8.1.2 Definitions ......................................................................................................................................... 8-3 8.2 General Information ..................................................................................................... 8-6 8.2.1 Comprehensive Plans, Codes, and Policies ................................................................................ 8-7 8.2.2 System Maps ...................................................................................................................................... 8-8 8.3 General Requirements .................................................................................................. 8-8 8.3.1 Standard Specifications and Plans ................................................................................................. 8-8 8.3.2 Regulations ........................................................................................................................................ 8-9 8.3.3 Industry Standards and other Agency Standards ..................................................................... 8-10 8.4 Basis of Design ............................................................................................................. 8-12 8.5 Design Process ............................................................................................................. 8-12 8.6 Other Design Disciplines ............................................................................................ 8-12 8.6.1 Structural ......................................................................................................................................... 8-12 8.6.2 Landscaping...................................................................................................................................... 8-12 8.6.3 Instrumentation and Control ...................................................................................................... 8-13 8.6.4 Pump Stations ................................................................................................................................. 8-13 8.7 Storm Drain Design .................................................................................................... 8-13 8.7.1 Hydrologic and Hydraulic Evaluation ......................................................................................... 8-14 8.7.2 Drainage Basins............................................................................................................................... 8-15 8.7.3 CAM 1180 Design Guidelines for Public Storm Drain Facilities .......................................... 8-16 8.7.4 Pipe Storm Drain ........................................................................................................................... 8-24 8.7.5 Maintenance Holes ........................................................................................................................ 8-31 8.7.6 Ditches and Culverts ..................................................................................................................... 8-37 8.7.7 Culverts in Streams and Intermittent Streams ........................................................................ 8-41 8.7.8 Water Quality Treatment ............................................................................................................ 8-42 8.7.9 Flow Control .................................................................................................................................. 8-43 8.7.10 Green Stormwater Infrastructure .............................................................................................. 8-44 8.7.11 Outfalls ............................................................................................................................................. 8-44 8.8 Sanitary Sewer Design ................................................................................................ 8-46 8.8.1 General ............................................................................................................................................. 8-46 8.8.2 Hydraulic Evaluation and Capacity Analysis ............................................................................. 8-47 8.8.3 Sanitary Sewer Basins .................................................................................................................... 8-47 8.8.4 Pipe Sewer Sanitary ....................................................................................................................... 8-47 8.8.5 Maintenance Holes ........................................................................................................................ 8-49 8.9 Combined Sewer Design ............................................................................................ 8-49 8.9.1 Hydrologic and Hydraulic Evaluation ......................................................................................... 8-50 8.9.2 Combined Sewer Basins ............................................................................................................... 8-50 8.9.3 CAM 1180 Design Guidelines for Public Storm Drain Facilities .......................................... 8-50 8.9.4 Pipe Sewer Combined ................................................................................................................... 8-50 8.9.5 Maintenance Holes ........................................................................................................................ 8-52 8.9.6 Outfalls ............................................................................................................................................. 8-52 8.9.7 Overflow Monitoring .................................................................................................................... 8-52 SPU Design Standards and Guidelines Chapter Owner: Kathy Laughlin December 2020 8-i Chapter 8 Drainage & Wastewater Infrastructure 8.10 Rehabilitation Methods Using Trenchless Technology ........................................... 8-52 8.11 Construction ................................................................................................................ 8-56 8.11.1 Alternative Construction Methods ............................................................................................ 8-56 8.11.2 Construction Stormwater Control ............................................................................................ 8-57 8.11.3 Bypassing Flow in Existing Sewer ................................................................................................ 8-58 8.11.4 Abandonment and Removals ....................................................................................................... 8-58 8.11.5 Acceptance Procedures ................................................................................................................ 8-58 8.11.6 Connecting to Existing Systems .................................................................................................. 8-59 8.12 Drainage and Sewage Easements .............................................................................. 8-59 8.13 Resources ..................................................................................................................... 8-61 Appendices Appendix 8A - Structural Calculations for Maintenance Holes Appendix 8B - Useful Figures and Concepts Appendix 8C - GSI Manual Appendix 8D - CAM 1180 Appendix 8E - Core Tap Procedures for Storm and Sewer Mains List of Figures Figure 8-1 Hydraulic Grade Line Requirements .................................................................................................... 8-26 Figure 8-2 Hanson Hole Size Chart ......................................................................................................................... 8-33 Figure 8-3 Maintenance Hole Sizing Methodology ................................................................................................ 8-34 Figure 8-4 Open Drop Connection for Maintenance Holes .............................................................................. 8-37 List of Tables Table 8-1 City Regulations for Drainage and Wastewater Facilities .................................................................. 8-9 Table 8-2 Partial List of Industry Standards and Specifications .......................................................................... 8-10 Table 8-3 Other Agency Standards.......................................................................................................................... 8-11 Table 8-4 Erosion Protection for Culvert Design ................................................................................................ 8-39 Table 8-5 Inlet/Outlet Protection Required Conditions at Given Velocities .................................................. 8-40 Table 8-6 Rehabilitation Methods for Specified Defects in Pipelines ................................................................ 8-53 Table 8-7 Advantages and Disadvantages of Lining .............................................................................................