Stormwater Manual

The City of Gig Harbor Stormwater Management and Site Development Manual is your complete guide to managing stormwater properly and meeting local and state requirements. Whether you're planning a project, managing a site, or operating a business, this manual has the tools you need to protect water quality and stay in compliance.

The manual is updated periodically to meet requirements of the city's NPDES Phase II Stormwater Permit issued by the Department of Ecology.

2023 City of Gig Harbor Stormwater Management and Site Development Manual

Full Manual

Manual Volumes:

Table of Contents

Glossary, Acronyms, and Notations

• Volume I - Minimum Technical Requirements and Site Planning
  • Appendix I-A Maintenance Checklists
  • Appendix I-B Wetland Protection Guidelines
  • Appendix I-C Underground Injection Control (UIC) Program Guidelines
• Volume II - Construction Stormwater Pollution Prevention
  • Appendix II-A Recommended Standard Notes for Construction Stormwater Pollution Prevention Plans
• Volume III - Hydrologic Anaylsis and Flow Control BMPs
  • Appendix III-A Methods for Determining Design Infiltration Rates
  • Appendix III-B Design Aids: Design Storm Precipitation Values, Isopluvial Maps, SCS Curve Numbers, Roughness Coefficients, and Soil Types
  • Appendix III-C Nomographs for Various Culvert Sizing Needs
  • Appendix III-D Onsite Stormwater Management BMP Infeasibility Criteria
• Volume IV - Source Control
  • Appendix IV-A Recycling/Disposal of Vehicle Fluids/Other Wastes
  • Appendix IV-B Example of an Integrated Pest Management Program
  • Appendix IV-C Recommendations for Management of Street Wastes
• Volume V - Runoff Treatment BMPs
  • Appendix V-A Geotextile Specifications
• Volume VI - Comprehensive Low Impact Development Site Designs

Attachments

• Section A - Quantity Design Details
• Section B - Quality Design Details
• Section C - Erosion and Sediment Control Plan Details
• Section D - Soil Evaluation Report Forms
• Section E - Standard Stormwater Notes
• Section F - Stormwater Facility Informational Sign Specifications
• Section G - Stormwater Maintenance Agreement