Widening I-85 Won’t Fix Traffic — It Will Waste $1.4 Billion

October 22, 2025

The North Carolina Department of Transportation (NCDOT) is preparing to spend a whopping $1.4 billion to widen about 10 miles of I-85 between Gastonia and Belmont.¹ That’s roughly $140 million per mile of new lanes.

Construction crews will begin closing lanes this Sunday night so engineers can study the area. Supporters say the expansion will reduce congestion. But decades of evidence show that widening highways doesn’t work. In fact, it makes traffic worse.

Why widening fails

Here’s what really happens every time a highway is widened:

At first, the new lanes make traffic move more easily. But soon, drivers who used to avoid rush hour start using the road again. People move farther from work because the commute seems faster. Businesses build farther out. Before long, the highway fills back up — and we’re right back where we started, often with even more traffic than before.

This well-documented pattern is called induced demand — when increasing road capacity leads to more driving. Studies show that for every 1 percent increase in lanes, vehicle traffic increases about 1 percent within a few years.²

Cities and states across the country have learned this lesson the hard way.

Houston’s Katy Freeway was widened to an unbelievable 26 lanes at a cost of $2.8 billion. Just three years later, commute times were worse than before.³
Los Angeles’ I-405 expansion cost $1.6 billion and resulted in slower rush-hour speeds than before construction.⁴

If billion-dollar widenings can’t solve congestion in cities like Houston and Los Angeles, there’s no reason to think they’ll work here.

Who benefits — and who pays

Every new highway widening is a windfall for the road construction and paving industry, whose lobbyists pressure lawmakers for more projects.

Meanwhile, taxpayers foot the bill, and residents deal with the side effects: more traffic, more crashes, more air pollution, and more sprawling development that makes car trips longer and costlier.

Each time we choose widening, we delay the investments that could actually give people choices — like safe sidewalks, bike networks, reliable transit, and smarter development that keeps housing and jobs closer together.

The better way forward

Instead of repeating the same mistake on I-85, NCDOT should:

Pause the I-85 widening study.
Develop a regional rail line alongside I-85 to connect Charlotte and the growing communities of Gaston County. A modern commuter rail corridor running parallel to the interstate would actually relieve congestion by giving thousands of residents a fast, reliable way to travel without driving — a real, long-term solution that highways can never provide.
Reallocate funds now earmarked for widening toward studying this rail option in partnership with the Federal Railroad Administration, which is already exploring a Charlotte-to-Atlanta passenger rail corridor that would connect cities across the Southeast.⁵

These are the strategies that reduce congestion for real — by giving people more space-efficient options.

The bottom line

Every place that has tried to build its way out of congestion by widening roads has failed. Our region deserves better than another billion-dollar highway that will fill up within a few years.

Let’s invest in proven solutions and say no to wasteful widening.

Sources

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