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

Use Code 25for25 at checkout for 25% off an annual plan!

Interior of Place Versailles mall in Montreal, Canada.

Montreal Mall to Become 6,000 Housing Units

Place Versailles will be transformed into a mixed-use complex over the next 25 years.

May 22, 2025 - CBC

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.

May 28, 2025 - Diana Ionescu

AI-generated image of high-speed rail trail in elevated track in green hilly farmland.

Four Reasons Urban Planners Can’t Ignore AI

It’s no longer a question of whether AI will shape planning, but how. That how is up to us.

May 28, 2025 - Tom Sanchez

Aerial view of Bend, Oregon.

Bend, Deschutes County Move to Restrict Major Homeless Encampment

City and county officials are closing off portions of an area known as Juniper Ridge where many unhoused residents find shelter, hoping to direct people to housing and supportive services.

May 30 - The Bulletin

Metro rail station in Mariachi Plaza with colorful glass pavilion in Boyle Heights, Los Angeles, California.

High Housing Costs Driving Down Transit Ridership in LA

When neighborhoods gentrify and displace lower-income residents, transit ridership suffers, new research shows.

May 30 - CALmatters

Des Moines, Iowa skyline viewed from a plaza with two flags on either side at dusk.

Iowa Legalizes Accessory Dwelling Units

A new law will allow property owners to build ADUs on single-family lots starting on July 1.

May 30 - Smart Cities Dive

Urban Design for Planners 1: Software Tools

This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.

Planning for Universal Design

Learn the tools for implementing Universal Design in planning regulations.