Washington Stormwater Management Study

The Washington Stormwater Management Study was completed in September 2001 and is available for for viewing or download. To reduce the document size for viewing or download, the main body of the report is provided separately from the appendices and perspectives.

Washington Stormwater Management Study

The Washington State Department of Transportation in collaboration with the Washington State Department of Ecology and the Stormwater Policy Advisory Committee elected to conduct a stormwater management study (Study) to develop stormwater management recommendations. This final report summarizes key findings of the study. It presents study themes, policy statements, and recommendations from the Stormwater Policy Advisory Committee.


These letters provide some additional information about perspectives on stormwater management that are not found in the main report. They are representative of the authors' perspective and were not subject to review by the Stormwater Policy Advisory Committee.

Appendix A - Definitions

This appendix includes definitions of terms in the Study that may not be commonly known or may have specific definitions within the context of the study. The italicized terms in the Study are defined in Appendix A.

Appendix B - Interview Questions and Stormwater Interrelations Matrix

Interviews were conduction to gather information about stormwater regulations and and programs. Information was recorded on the interrelations matrix. This appendix lists the questions, the proposed entities for interviews and provides a copy of the matrix.

Appendix C - Interview Results Summary

Appendix C provides an abbreviated summary of the results of stakeholder interviews. The interview questions were recommended by the Stormwater Policy Advisory Committee (SWPAC). The interviewee answers formed the basis for themes and potential recommendations to the 2001 Washington State Legislature. Where multiple respondents have agreed on a statement, this concurrence is noted.

Appendix D - Stormwater Management Cost Information

Appendix D provides a summary of the available cost information for stormwater management programs in Washington. Estimates of stormwater program costs were compiled from stakeholder interviews, information provided by stakeholders, and selected literature sources containing cost information. A wide range of costs was quoted from these sources; no quality assurance or validation of these cost estimates was conducted.

Appendix E - Table E-1

Comparison of regulatory requirements in matrix format.

Appendix F - Matrices: Stakeholder Perception and Program Owners

Text and matrices of stormwater management regulatory relationships as identified by:

Appendix G - Stormwater Program Summaries

Provides information about stormwater programs including the goals and policies of the different programs. The programs presented are:

Appendix H - Summary and Analysis of Stormwater Regulations and Programs

This appendix provides a summary and analysis of regulations and programs in Washington State that are either directly or indirectly related to stormwater management. This information was compiled from federal or state agency publications, or through interviews with the "program owners" (those agencies in charge of administering and/or enforcing the regulations). It covers the same programs as Appendix G

Appendix I - Recommendations for Stormwater Regulations and Programs

This appendix summarizes the findings of Task 3, as described in the scope for Part 2 of the Stormwater Management Study. These findings clarify and augment the Stormwater Policy Advisory Committee’s recommended improvements to existing stormwater regulations and programs, as initially put forth in the Stormwater Management Study Final Interim Report to the Washington State Legislature (December 2000). It includes a summary of additional research and analysis conducted under Tasks 1, 2, and 3, input from the Stormwater Management Study Steering Committee, and new and/or revised policy statements and recommendations.

Appendix J - Compensatory Mitigation for Stormwater

This appendix discusses on-site mitigation, advanced mitigation (banking) and environmental credit trading approaches. It provides an evaluation of these approaches to stormwater management.

Appendix K - Communications Plan and Training Program

This appendix proposes a communications plan that outlines activities, materials, and strategies that could, when implemented, function as an integrated communications program and provide the needed communications support for stormwater management in Washington State. The appendix concludes with an outline of a training program using PowerPoint slides.

Appendix L - Fact Sheet

A fact sheet that could be used as a handout. It is produced as an 11 x 17 front and back tri-fold.

Appendix M - References