SR 520 Pontoons and Floating Bridge and Landings

For the SR 520 Pontoon Construction Project in Aberdeen and the SR 520 Evergreen Point Floating Bridge and Landings Project (SR 520 FBL Project) in Lake Washington, Floyd|Snider supported both of the Design-Build Teams by providing environmental permitting and hazardous materials characterization services. The design-build contracts include the construction of a new six-lane floating bridge, demolition of the existing floating bridge, and construction of a casting basin and bridge pontoons in Aberdeen, Washington. As part of the SR 520 FBL Project, a new east approach connection to the bridge will also be constructed, along with a new Washington State Department of Transportation (WSDOT) bridge maintenance facility and dock. The combined value of the construction contracts is $953 million. Completion of the construction of the new bridge is anticipated in December 2014.

Floyd|Snider was permit lead for acquisition of all Design-Builder permits and agency coordination, and works with the project team to ensure that work is conducted consistent with permit conditions, applicable regulations, and environmental requirements by documenting these requirements in Environmental Compliance Plans for each project. Floyd|Snider supported the project team's design interpretation of environmental impacts to assist WSDOT with acquiring National Environmental Policy Act (NEPA) clearance and state-led project permits, and State Environmental Policy Act (SEPA) and NEPA analyses based on Kiewit-General's specific design. Floyd|Snider worked closely with the design-builder, as well as the design engineers for both projects, HNTB for the Pontoons Project and KPFF for the SR 520 FBL Project, to strategically prepare permit application submittals that maintained flexibility as the project designs were finalized, while ensuring that project impacts were consistent with design-builder and WSDOT environmental requirements. Floyd|Snider developed monitoring and protection plans under the 401 Water Quality Certification, acquired National Pollutant Discharge Elimination System (NPDES) stormwater permits, building permits, noise variances, PATON navigation permits, and coordinated provision of design information to WSDOT for NEPA re-evaluation and Joint Aquatic Resource Permit Application (JARPA) permitting for the projects.


  • Environmental Permitting
  • Hazardous Materials Characterization Services