U.S. Coast Guard approval of a fixed-span design for a new Interstate Bridge marked a key regulatory step forward last week, but soaring costs have clouded the project’s outlook.
Cost estimates for the Interstate Bridge replacement program have more than doubled, with a high-end estimate for a fixed span rising to $17.7 billion, according to recently unearthed Oregon Department of Transportation documents.
The documents were obtained by City Observatory, a Portland-based think tank, through a public records request. ODOT hadn’t publicly updated its cost estimates since 2022, when it gauged the bridge’s cost at $5 billion to $7.5 billion…