Oregon’s proposal to widen Interstate 5 through the Rose Quarter is one of the nation’s 9 worst highway boondoggles, according to a report from two nonprofit environmental think tanks released Tuesday.

The proposed roughly $500 million project to add merging lanes and shoulders to I-5 on a one-mile stretch of freeway between two other interstates is a mega-project that won’t fix traffic woes, won’t make the area safer for motorists, and will damage the environment, according to the report from the Frontier Group and U.S. PIRG Education Fund. The organizations are nonprofit think tanks that focus on financial oversight, both frequently work ob environmental issues.

“In Portland, a city that has taken great strides toward more sustainable transportation, an expensive highway project would constitute a step backward to the car-dependent policies of the past,” the report said of the Rose Quarter proposal. “It would also likely fail to meaningfully improve safety compared with other investment strategies.”

The 42-page report highlights proposed freeway projects in North Carolina, Texas, California, Michigan, Illinois, Florida, Pennsylvania and Virginia as emblematic of a worrisome trend of mega-expansions that “absorb billions of dollars of scarce public funds while delivering few benefits.” The report estimates the 9 projects named total $25 billion and will saddle the states with additional debt “while likely failing to achieve meaningful transportation goals.”

The report cites Portland’s “bold moves” to expand its bikeshare program, remove on-street parking in some instances and create new higher capacity bus lines like the Division Transit Project as evidence of ways the city is embracing how to get people around without using a car.

But the state is taking a different step with the Rose Quarter plan. “An expanded highway will also likely increase carbon emissions, hindering Portland’s ability to achieve its emission reduction goals. ODOT’s own environmental assessment actually projects that the project will result in slightly reduced emissions,” compared with not building the project at all.

The report also argues that the project elements designed to improve street-level access for pedestrians and cyclists “are both inadequate and outweighed by the adverse effects of a bigger highway.”

The project is still in the design phase, and much of the specifics remain undecided, including whether the state can build freeway caps that can accommodate buildings on top of them.

Just last month, the state said it would hire a consultant to evaluate how to build “better define the length, and strength characteristics for the highway covers currently planned for the Project, and to openly describe the impacts and benefits of several different highway cover configurations.

Don Hamilton, a spokesman for the state’s transportation department, said the project “will upgrade all forms of transportation in a congested corridor.”

“It will add new highway crossings for people walking and riding bicycles, remove seismically deficient overpasses, improve community access to transit, improve connections for neighborhoods divided for a half century by I-5, add new safety shoulders and auxiliary lanes on I-5, reduce freeway crashes, and reduce congestion by an estimated 2.5 million hours per year,” he said in an email.

The Rose Quarter is the second-cheapest project included on the group’s boondoggle list. A $300 million proposal to widen Interstate 83 in Pennsylvania is the cheapest project included. An $8 billion project in California called the High Desert Freeway is listed as the most-expensive proposal.

Frontier and U.S. PIRG suggest government officials should reevaluate the projects “in light of changing transportation needs” and invest in public transportation, congestion pricing and prioritize projects that result in lower vehicle miles traveled rates nationwide.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen

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