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

portrait of professional woman

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

Cover CM Credits, Earn Certificates, Push Your Career Forward

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

June 11, 2025 - Diana Ionescu

Metrorail train pulling into newly opened subterranean station in Washington, D.C. with crowd on platform taking photos.

Congressman Proposes Bill to Rename DC Metro “Trump Train”

The Make Autorail Great Again Act would withhold federal funding to the system until the Washington Metropolitan Area Transit Authority (WMATA), rebrands as the Washington Metropolitan Authority for Greater Access (WMAGA).

June 2, 2025 - The Hill

Large crowd on street in San Francisco, California during Oktoberfest festival.

The Simple Legislative Tool Transforming Vacant Downtowns

In California, Michigan and Georgia, an easy win is bringing dollars — and delight — back to city centers.

June 2, 2025 - Robbie Silver

Man in teal shirt opening door to white microtransit shuttle with cactus graphics and making inviting gesture toward the camera.

Albuquerque’s Microtransit: A Planner’s Answer to Food Access Gaps

New microtransit vans in Albuquerque aim to close food access gaps by linking low-income areas to grocery stores, cutting travel times by 30 percent and offering planners a scalable model for equity-focused transit.

June 13 - U.S. Department Of Transportation

Group of people at table set ouf with picnic food on street during a neighborhood block party.

This City Will Pay You to Meet Your Neighbors

A North Kansas City grant program offers up to $400 for residents to throw neighborhood block parties.

June 13 - The Kansas City Star

Crowd gathered with protest signs on April 5, 2025 on steps of Minnesota state capitol protesting Trump cuts to social security and other federal programs.

Commentary: Our Silence Will Not Protect Us

Keeping our heads down and our language inoffensive is not the right response to the times we’re in. Solidarity and courage is.

June 13 - Shelterforce Magazine