February 11, 2011 - Amendment to state rules changes the wetland delineation manual
Changes to the state wetland delineation manual became effective on March 14, 2011. Read more about the changes.
Wetland delineation establishes the existence (location) and physical limits (size) of a wetland for the purposes of federal, state, and local regulations.
Wetland delineation is also an element of a “jurisdictional determination.” This process identifies which water bodies within a project's boundaries meet the definition of "waters of the United States." For more information on this, see the Corps' Regulatory Guidance Letter 08-02, Jurisdictional Determinations (issued June 26, 2008, PDF 118 kb).
Remember that the Corps of Engineers (Corps), not applicants or their consultants, determines whether or not a wetland is a "water of the United States" and thus regulated under the federal Clean Water Act (CWA). If the Corps determines that a wetland is not subject to the CWA, the wetland may still be a "water of the State" and subject to regulation by Ecology as well as by local jurisdictions. Ecology regulates wetlands determined by the Corps to be non-jurisdictional due to their isolation from navigable waters. > More on Isolated Wetlands
The Corps now requires you to use the appropriate regional Supplement when delineating wetlands:
A report that explains how the boundary was determined. It should include:
A description of how and when the delineation was done
Data forms used to delineate the wetland area
The map described in #2 above
A soil survey map.
Delineation checklist (PDF) -a checklist of information that should be in your wetland delineation report, as well as a sample report outline.
NOTE: You may need to hire a qualified wetland professional to
identify and delineate wetlands (using the manuals listed above) and prepare a
> Hiring a Qualified Wetland Professional (PDF) -tips to help you find and select a qualified wetland professional.
If you have any questions about wetland delineation, contact:
Tom Hruby, PhD
Washington State Department of Ecology
P.O. Box 47600
Olympia WA 98504
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