The
Interstate Bridge Replacement Program is proposing to replace the I-5 Interstate Bridge that crosses the Columbia River to connect Portland, Oregon and Vancouver, Washington.
The project would replace the existing northbound and southbound interstate bridges with two new parallel single-level fixed-span bridges. Of the two new bridges, the new eastern (upstream) bridge would accommodate northbound highway traffic and a bicycle and pedestrian path. The new western (downstream) bridge would carry southbound traffic and be designed to facilitate the future integration of a two-way light rail public transit system.
The Interstate Bridge Replacement Program anticipates that construction will begin in 2028, depending on regulatory permit approvals and other factors.
Public engagement – proposed water quality certification
The Oregon Department of Environmental Quality invites the public to attend a hearing and submit verbal or written comments on a proposed issuance of a Section 401 water quality certification for the Interstate-5 Bridge Replacement Project, known officially as a Clean Water Act Section 401 water quality certification.
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See the public notice. The public notice includes information and draft
documents on the proposed certification and provides details on how to submit a
comment.
Submit written comments to DEQ by
Thursday, Aug. 6, 2026, at 5 p.m.
Virtual public hearing: Thursday, July 30, at 6 p.m.
Register for the Zoom Webinar
Call-in number: 888-475-4499
- Webinar ID: 858 7734 2181
- Passcode: 258360
Water quality permit requirements
Water quality certification
DEQ received a request for a Section 401 water quality certification on Feb. 17, 2026. This certification is part of the federal 404 authorization process administered by the U.S. Army Corps of Engineers. The federal Section 404 program regulates activities in waters of the United States, like the Columbia River. DEQ reviews these projects to ensure they meet state water quality standards and sets requirements to protect water quality.
DEQ will only issue a Section 401 water quality certification decision for the work proposed in Oregon.
A state-issued Section 401 water quality certification is a required component of this federal permitting process. It must be obtained before the federal 404 permit can be authorized. The U.S. Army Corps of Engineers is the lead regulatory agency for the 404 authorization process.
Stormwater
A stormwater permit called a National Pollutant Discharge Elimination System, or NPDES, permit is also required for the project. The permit will manage stormwater discharged from the site during construction in Oregon. DEQ will publish a public notice that includes a public comment period and draft permit documents when it's ready.
Documents and resources