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' of Engineers (Corps) Regulatory Guidance Letter 08-02, Jurisdictional Determinations.
Remember that the 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
Generally, any delineation done over five years ago needs to be revisited. This is due to several factors:
Revisiting a wetland delineation that is five or more years old does not necessarily mean that a new wetland delineation needs to be done. It means that it may be necessary to revisit the site to determine whether the delineation is still accurate or whether it needs to be redone based on current conditions. Consult with the agencies to discuss your specific wetland delineation.
The Corps now requires you to use the appropriate regional supplement when delineating wetlands:
See Ecology's delineation checklist (PDF) for a detailed list 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 help you identify and delineate wetlands (using the manuals listed above) and prepare a delineation report. See Hiring a Qualified Wetland Professional for tips to help you find and select a qualified wetland professional.
If you have any questions about wetland delineation, contact the regional wetland specialist for your area.
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