Benefits Harder to Recognize as Costs to Widen the I-405 Rise

Was the I-405 widening project worth it for Los Angeles? Depends on whom you ask.

2 minute read

December 22, 2016, 11:00 AM PST

By James Brasuell @CasualBrasuell


405 Traffic

Bart Everett / Shutterstock

Adam Nagourney performs a post-mortem of sorts on the widening of the 405 Freeway in Los Angeles, which hasn't been able to escape the news as costs continue to skyrocket (the most recent spate of unexpected expenses puts the cost of the project up to $1.6 billion) and benefits to drivers have been scant or nonexistent.

The question examined by Nagourney on behalf of many in the state and region: Was it worth it?

The data tell a distressing story about the project's effect: "Peak afternoon traffic time has indeed decreased to five hours from seven hours’ duration (yes, you read that right) and overall traffic capacity has increased. But congestion is as bad — even worse — during the busiest rush hours of 4:30 to 6:30 p.m." That dose of induced demand is verified by a study undertaken by the Los Angeles County Metropolitan Transportation Authority (Metro).

Some in positions of power, like the current head of Metro, Philip Washington, say the project delivered benefits in capacity and safety. Critics point out that news of the project's continued cost overruns was delayed to the political benefit of Measure M—a sales tax approved by voters in November.

If there's one thing that can assuage the guilt of Los Angeles political leaders and voters who might regret the project, it's that the 405 is not the only example of a major highway project failing to deliver the desired congestion relief. An expansion of the I-10 Katy Freeway in Houston also induced demand to the detriment of travel times at costs involving the word billion.

Tuesday, December 20, 2016 in Los Angeles Times

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