WSDOT Mukilteo Multimodal Ferry Terminal Environmental Impact Statement

The Washington State Department of Transportation (WSDOT) considered sea-level rise as a factor in early design and environmental review for the Mukilteo Multimodal Terminal Project (“Project”). The Project will develop a new terminal for the Mukilteo/Clinton Ferry, which provides transportation between Whidbey Island and the Seattle metropolitan area. In the final Environmental Impact Statement (EIS) for the Project, WSDOT acknowledged that changing climate would impact the function and operations of Multimodal Project over the 50 to 100 year lifespan of the facility. The Selected Alternative for the facility will provide more opportunities to accommodate anticipated sea-level rise, compared to other alternatives analyzed.   

The Washington State Department of Transportation released the final Environmental Impact Statement for the Mukilteo Multimodal Project in June 2013. The WSDOT Ferries Division, or Washington State Ferries (WSF), and the U.S. Federal Transit Administration (FTA) performed the environmental review for the project.  After analyzing multiple scenarios for a redevelopment, including a No Build Alternative and a proposal for Existing Site Improvements, Elliott Point 2 was chosen as the Preferred Alternative, and was approved as the Selected Alternative in the 2014 Record of Decision issued by FTA.  Both the No-Build and Existing Site Improvements alternatives for the terminal, as well as surrounding land uses and access streets, are located within the 100-year floodplain.  In contrast, the Preferred Alternative proposes building a new multimodal terminal one third of a mile east of the existing site, allowing facilities and access roads to be located outside the floodplain.  The Preferred Alternative would also allow the use of fill to modify terminal elevation above the floodplain, and therefore provide better resilience to sea-level rise and increased storm surge than the No-Build or Existing Site alternatives.

The current sea-level rise projection for Puget Sound is a range of 2 to 4 feet by 2100.  Additional projected regional effects of climate change include increased temperatures and heat events, worsened air quality, coastal erosion, salt water intrusion, ecological impacts on plant and animal habitats, and changes in precipitation, including more severe flooding and erosion (EIS 4-136).  The WSF and FTA used climate projections from the Climate Impacts Group at the University of Washington.

The recognition of future climate impacts is part of a broader policy objective in Washington. State agencies, including the WSDOT, have developed an “integrated climate response strategy” to incorporate climate adaptation in the design and analysis of capital projects.

The Mukilteo/Clinton Ferry provides service to nearly 4 million riders and over 2 million vehicles each year.  However, the multimodal terminal has not been upgraded since the 1980s and the facility does not fully meet current seismic standards. Total cost of the project is projected at $129 million, with funding from both state and federal sources. The FTA provided funding for the planning of the project, and may continue funding project construction. Phase 1 of construction, which was completed in February 2016, involved removing the old tank farm pier and preparing the site for the new terminal. WSDOT expects to complete the final design stages for the terminal in 2016, and construct the terminal and other facilities (Phase 2) between 2017 and 2019.


This Adaptation Clearinghouse entry was prepared with support from the Federal Highway Administration. This entry was last updated on March 22, 2016.


Publication Date: June 2013

Related Organizations:

  • Washington State Department of Transportation


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