1.2 How to Use this Manual

This manual provides the standards to be used for stormwater management planning and design for new and redevelopment projects, in accordance with Chapter 12.04 KCC. The manual is organized into two volumes, as follows:

1. Volume I: Project Minimum Requirements and Site Planning – Provides standards and information on how to apply the minimum requirements contained in the Stormwater Code. It also describes the site assessment and planning steps and requirements for drainage review submittals.

2. Volume II: Technical Requirements – Provides design standards and requirements to clearly identify for applicants the format and technical support data necessary for the development of consistent and complete design plans. Volume II contains the following chapters:

   • Chapter 1 — Plans and Reports
   • Chapter 2 — Construction Stormwater Pollution Prevention
   • Chapter 3 — Source Control of Pollution
   • Chapter 4 — Conveyance System Analysis and Design
   • Chapter 5 — Stormwater Management BMPs
   • Chapter 6 — Wetlands Protection
   • Chapter 7 — Operation and Maintenance
   • Chapter 8 — Critical Drainage Areas
   • Chapter 9 — Grading

This manual, including both volumes, is intended to be used in conjunction with several other relevant design manuals, including:

• Stormwater Management Manual for Western Washington (Ecology Manual) by the Washington State Department of Ecology Water Quality Program, July 2019

• Low Impact Development Technical Guidance Manual for Puget Sound (2012 LID Technical Guidance Manual) by Hinman and Wulkan, December 2012

• Highway Runoff Manual by the Washington State Department of Transportation, April 2019

• Hydraulics Manual by the Washington State Department of Transportation, April 2019

• Rain Garden Handbook for Western Washington: A Guide for Design, Installation, and Maintenance (Rain Garden Handbook) by Hinman et al., June 2013

The guidance provided in this manual supersedes the above referenced manuals in the event of conflicting guidelines or standards. The referenced manuals are prioritized in the order they are listed above, with the highest priority given to the Ecology Manual and the lowest priority given to the Rain Garden Handbook for Western Washington Homeowners. This manual will direct the user to the appropriate sections in these or other relevant manuals where applicable.