Study: Cost of Expanding Roads Outweighs Benefits

New research shows that the economic benefits of roadbuilding projects don’t come close to exceeding most projects’ costs.

2 minute read

September 8, 2024, 5:00 AM PDT

By Diana Ionescu @aworkoffiction


Aerial view of road construction with yellow heavy equipment parked next to two-lane asphalt road against green forest and blue sky

tamas / Adobe Stock

A new study published in the Journal of the American Planning Association highlights the high cost and low return of road expansion projects in urban areas, reports Maria Clara Cobo in Bloomberg CityLab. According to the study, the monetary value of purported time savings doesn’t have “anything close to the economic benefits that state and federal policymakers hope for.”

As Cobo explains, “The researchers considered several kinds of costs: They looked at direct government spending on roads, external costs such as pollution and traffic deaths and the value of roadway land that could otherwise be used for different purposes like housing, shops or public space.” When accounting for direct government spending alone, costs exceeded benefits by 17 percent.

However, the study focused on a new assessment of land value and how much space is dedicated to roadways, which adds significantly to the total cost of road projects. “Their estimate finds that roads account for a fifth to a quarter of all urbanized land in the US — that’s equal to the total area of West Virginia.” This land is valued at roughly $5.4 trillion in today’s dollars.

The research contradicts the popular belief — and assessments by the U.S. Department of Transportation (USDOT) — that highway widening projects benefit local economies. Moreover, “[The study finds] that reducing roadway area by 10% would yield a net benefit of nearly $28 billion a year.”

Wednesday, September 4, 2024 in Bloomberg CityLab

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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