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 $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 have already started closing lanes at 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 often 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.

Closer to home: what Charlotte shows us

We don’t have to look far to see that widening doesn’t solve congestion.

When I-485 in south Charlotte was expanded a few years ago, drivers hoped for a smoother commute. But even before construction finished, data showed travel times were already unreliable. During busy hours, trips could take two to six times longer than during off-peak times. After the widening opened, traffic quickly filled the new lanes.⁵

And this pattern continues all around our region.

NCDOT’s own data shows that on major roads like I-485 near Rocky River Road, traffic jumped from about 82,000 vehicles per day in 2022 to a projection of 134,000 by 2032 — despite multiple recent widenings.⁶

Even the agency’s own engineers and planners admit that as population grows, these projects only provide short-term relief.⁷

So why do we keep spending billions to repeat a strategy that fails every time?

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, North Carolina should:

Invest in fast, frequent transit — including bus rapid transit and future rail lines.
Build complete networks of sidewalks and bike lanes so short trips don’t require a car.
Make streets safer for everyone who uses them.
Encourage compact, connected neighborhoods so we spend less time driving in the first place.
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 Amtrak, which is already exploring a Charlotte-to-Atlanta passenger rail corridor that would connect cities across the Southeast.⁸

These are the strategies that reduce congestion for real — by giving people options.

Your vote can help change course

Right now, Mecklenburg County voters have a chance to reshape our region’s transportation future. The one-cent transportation sales-tax referendum on the ballot will fund transit, biking, walking, and street-safety improvements across our county.

Voting YES will move us toward a transportation system that actually works — instead of pouring $1.4 billion into a project that will clog right back up.

At the same time, we call on NCDOT and state lawmakers to pause the I-85 widening study, fully account for its long-term costs, environmental impacts, and induced demand, and reallocate funding to study construction of regional rail instead of more lanes.

The bottom line

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

Let’s invest in freedom of choice — the freedom to walk, bike, ride rail or bus, or drive safely and efficiently — instead of repeating a failed formula from the past.

Let’s vote YES for real solutions and say no to wasteful widening.

Sources

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