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Shoreline Management Act jurisdiction

The Shoreline Management Act (SMA) applies to:

• All marine waters below the ordinary high water mark
• Rivers with a mean annual flow greater than 20 cubic feet per second
• Lakes and reservoirs greater than 20 acres in area
• Shorelands and associated wetlands
• Shorelines of Statewide Significance (SSWS)

See the Shoreline Jurisdiction chapter of the SMP Handbook for guidance on designating shoreline jurisdiction. Download Chapter 5 (PDF).

TIP: Always include appropriate disclaimers on maps depicting shoreline jurisdiction. For example, "Shoreline jurisdiction boundaries depicted on this map are approximate. They have not been formally delineated or surveyed and are intended for planning purposes only. Additional site-specific evaluation may be needed to confirm/verify information shown on this map. An example of more generic language that might apply to all maps: "USE OF THIS MAP IMPLIES THE USER’S AGREEMENT WITH THE FOLLOWING STATEMENT: __________(jurisdiction) disclaims any warrantee of merchantability or warrantee of fitness of this map for any particular purpose, either expressed or implied. No representation or warranty is made concerning the accuracy, currency, completeness or quality of data depicted on this map. Any user of this map assumes all responsibility for the use thereof, and further agrees to hold ___________(jurisdiction) harmless from and against any damage, loss, or liability arising from any use of this map.

Some other key geographic terms and concepts related to shoreline management:

• Ordinary High Water Mark
• Adjacent Lands
• Floodway
• Federal and tribal lands and activities
• Channel migration zones

Note on alterations of shoreline conditions

Naturally occurring and manmade alterations of the shoreline result in modifications in the boundary of shoreline jurisdiction where the action changes the Ordinary High Water Mark or the other physical characteristics that determine jurisdiction of the SMA. Examples of such alterations include permitted manmade changes such as land-filling and dredging, flood control projects, and natural changes due to landslides, flooding, channel alterations, or river course changes. See RCW 90.58.020.

For more information

Law: 90.58.030(2) (see Definitions)

Rules:

• Rivers: WAC 173-18
• Lakes: WAC 173-20
• Shorelands and Associated Wetlands: WAC 173-22

WAC's 173-18, 20, 22, and 27 were recently amended to clarify procedures for documenting the jurisdiction of the Shoreline Management Act within shoreline master programs. The rules were also updated to be consistent with recent amendments to the Shoreline Management Act. Click on the links to view the new rules.