I-405 - SR 522 Vicinity to SR 527 Express Toll Lanes Improvement Project - Environmental Assessment

WSDOT and the Federal Highway Administration issued the Finding of No Significant Impact and Errata for the I-405, SR 522 Vicinity to SR 527 Express Toll Lanes Improvement Project on July 29, 2021.

WSDOT and FHWA published the Environmental Assessment for the I-405, SR 522 Vicinity to SR 527 Express Toll Lanes Improvement Project on July 2, 2020. The comment period ended on August 6, 2020.

The State Environmental Protection Act (SEPA) Determination of Non-Significance (pdf 68.41 kb) for the Project was also published on July 2, 2020.

Documents for download

What is an Environmental Assessment?

The Environmental Assessment describes the purpose and need of the project and provides to the public and decision makers about environmental effects and benefits of the project.

The EA compares future effects if WSDOT did or did not build the project and provides a detailed analysis of the proposed project’s effects.