Click the colored icons in the map to find more information on specific SR 520 mitigation projects.
When planning transportation projects, WSDOT first seeks to avoid or minimize adverse effects to the environment. If a project has unavoidable effects, we must mitigate for those effects. To mitigate for effects to parks, wetlands and aquatic resources associated with the I-5 to Medina project, we have conducted mitigation activities at several sites. Because SR 520 reconstruction is occurring in phases, additional mitigation projects are pending. You can find more information about our mitigation activities by clicking on the individual sites shown on the above map.
To identify these mitigation sites, WSDOT has undertaken a comprehensive screening process in coordination with local, state and federal regulatory agencies, stakeholders, and tribes. Opportunities for on-site mitigation have been maximized to the extent possible. However, on-site mitigation is limited by existing land use, high-density development surrounding the project area, and overall insufficient area available for mitigation. WSDOT restores construction-related impacts on-site. For any remaining unavoidable temporary or permanent impacts, WSDOT conducts mitigation at off-site locations.
Additional information on the natural resources mitigation planning process and proposed wetland and aquatic mitigation sites can be found in the Wetland Mitigation Plan and Aquatic Mitigation Plan.