Description: Shoreline Master Plan for Thurston County, WA. Thurston County's dataset that defines environmentally sensitive areas. The purpose of this data is to aide planners and permit center personnel in determining environmental impacts on property. This layer is used as a screening tool and the informaiton is based upon the Shoreline Master Program for the Thurston Region Effective May 15, 1990. Updated by kah on May 25, 2016