US Army Corps of Engineers
Seattle District

Electronic Permit Guidebook

               Click here for permit information 

     Click here for permit information

Streams, Rivers, and Tidal Waters

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Headwater streams are the small swales, creeks and streams that are the origin of most rivers. These small streams join together to form larger streams and rivers or run directly into larger streams and lakes. Streams may be home to small fish, amphibians and invertebrates.

Streams can be ephemeral, intermittent or perennial. Ephemeral streams are those that contain flowing water only after major rain events or for very short times during the year. Intermittent streams flow only during the wetter periods of the year. Perennial streams contain water year-round. The collective health and functioning of the stream network have profound influences on the quality and value of larger streams, rivers and lakes.

Compensatory stream mitigation may be required for impacts to streams and should be designed to restore, enhance, and maintain stream uses that are adversely impacted by authorized activities.

If you are performing work in tidal waters in Washington State, you must identify the limits of the Corps jurisdiction. Under Section 10 of the Rivers and Harbors Act, the limits of the Corps' jurisdiction is the line of Mean High Water.  Under Section 404 of the Clean Water Act, the limits of the Corps' jurisdiction is the High Tide Line (HTL).  As a resource when determining the HTL, please see the tidal datums listed on this NOAA website (select nearest Benchmark listed in Washington State closest to your project site, then select tab for "Tides/Water Levels", then scroll down to "Datums") to determine if your proposed project is within the jurisdictional limits of the Corps.  If the activity is within these limits then a permit from the Corps is required.  These lines of jurisdiction must be shown on permit application drawings submitted to the Corps.


Please utilize this list to help you identify which waterways of Washington State are considered to be navigable waters of the U.S.

Some waterways are considered to be "traditional" navigable waters even if they are not on the Navigable Waterway List described above. This list describes some of these types of waters of the U.S.

The National Wild and Scenic Rivers System was created by Congress in 1968 to preserve certain rivers with outstanding natural, cultural, and recreational values in a free-flowing condition for the enjoyment of present and future generations. The Act is notable for safeguarding the special character of these rivers, while also recognizing the potential for their appropriate use and development. Please visit this website for more information on which waterways are designated Wild and Scenic Rivers.