Interagency Wetland Mitigation Guidance

Wetland Mitigation in Washington State, Version 1, is a two-part interagency document providing guidance on wetland mitigation. You can access the mitigation guidance document (Parts 1 and 2) below. Due to the dynamic nature of wetland science and regulatory frameworks, the guidance found in the document is subject to revision. The most current version is the March 2006, Version 1.  The most current version will always be available on this web page. We will also notify those on our Wetland Information Listserv when updates to the document are made. If you are interested in why, when, and how the document was developed you can read the background information.

Part 1 - Agency Policies and Guidance

Part 1 provides a brief background on wetlands, an overview of the factors that are considered in the agencies' permitting decisions, and detailed guidance on the agencies' policies on wetland mitigation, particularly compensatory mitigation. It replaces the portions of the 1997 Ecology publication, How Ecology Regulates Wetlands (Publication #97-112), pertaining to wetland mitigation.

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Part 2 - Developing Mitigation Plans

Part 2 provides technical information on preparing plans for compensatory mitigation. It updates and replaces the 1994 Guidelines for Developing Freshwater Mitigation Plans and Proposals (Publication #94-29).

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Links to More Guidance

Monitoring Guidance

The U.S. Army Corps of Engineers (Corps) issued a Regulatory Guidance Letter to clarify monitoring requirements for compensatory mitigation projects.  The Corps, Seattle District, has incorporated the most recent Regulatory Guidance Letter (RGL) 08-03 into their monitoring requirements for compensatory mitigation projects. > More on Compensatory Mitigation Monitoring Requirements.

Mitigation that Works

We are in the process of developing a number of guidance documents with the goal of improving mitigation.  For example, in 2009 and 2010, Ecology published guidance on Selecting Wetland Mitigation Sites Using a Watershed Approach for both eastern and western Washington.  This and all other mitigation guidance is available on Ecology's Mitigation that Works resources web page.  We make announcements about the availability of any new guidance to the Wetlands Information Listserv.

If you have any questions contact Dana L. Mock, 360-407-6947.


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