How to Determine the Ordinary High Water Mark in Eastern WA

WA State Department of Ecology/The Padilla Bay NERR


Thursday, April 13, 2017, 9 a.m.
Friday, April 14, 2017, 4 p.m. PDT

Spokane, WA, United States

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This training provides information and methods for determining the ordinary high water mark (OHWM) as defined in the state Shoreline Management Act (SMA).  Waters regulated under the SMA include all tidal waters, streams greater than 20 cubic feet per second mean annual flow, water bodies greater than 20 acres in size and any associated wetlands and deltas.  Field visits to each of the SMA water types will give you the opportunity to apply the methods discussed in the classroom.        


In this training, you will learn answers to these questions:      

- How is the OHWM defined and where does it apply?

- What is the regulatory context and history of the OHWM?

- Why it is important to use field indicators to determine the OHWM?

- What are the most reliable field indicators on streams, lakes and associated wetlands?

- What are some common misconceptions about OHWM determinations?

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Paul Anderson

Paul Anderson is certified as a Professional Wetland Scientist and has been working in natural resource management since 1990. He has been a wetland specialist at Ecology’s Northwest Regional Office since July 2006. Paul is responsible for jurisdictions within Snohomish, Skagit, and San Juan counties. His duties include reviewing ... Read More

Lynn Schmidt

Lynn Schmidt is the Department of Ecology’s Statewide Flood Engineer, focusing on reducing flood risks to communities while enhancing natural floodplain functions. Her career has spanned a wide range of topics within the environmental and hydraulics engineering fields, including hydraulic modeling, river restoration, floodplain management, stormwater management, environmental investigations ... Read More

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Cathy Angell,