Why Widening Freeways Is Making Traffic and Climate Worse — Not Better

Across America, traffic is brutal. Commutes are long, roads are clogged, and frustration is sky-high. So what’s the typical response? Build more lanes. Add more freeway capacity. Spend billions trying to “relieve congestion.”

But here’s the truth: It doesn’t work. It never has. And it’s making things worse — for our cities, our climate, and our future.

More Lanes = More Cars = More Emissions

This idea might seem counterintuitive, but it’s backed by decades of data. When you add lanes to a freeway, you don’t fix traffic — you invite more of it. This is called induced demand: when driving becomes temporarily easier, more people start doing it. Trips they once avoided now seem convenient. People move farther out. Sprawl spreads.

Look at Los Angeles, where thousands of people commute two hours each way from places like Riverside just to find affordable housing. Widening the 405 didn’t help. Adding capacity only encouraged more long-distance driving and more time behind the wheel.

The Carbon Cost Nobody Talks About

More cars on the road means more CO2 — even as electric vehicles grow. But there’s another layer most people forget: building freeways is a carbon-intensive process. It involves cement, asphalt, diesel-fueled machinery, and the destruction of natural land.

And once new roads are built, they fuel sprawling development — which leads to even more driving. It’s a vicious cycle.

Example? The Katy Freeway in Houston was expanded to a staggering 26 lanes. The result? Longer commute times and worse congestion than before. Emissions skyrocketed.

What If We Did the Opposite?

Instead of throwing more asphalt at the problem, what if we made the bold move to stop expanding — or even reduce — freeway capacity?

Here’s what would happen:
- Driving becomes less convenient — and that’s a good thing.
- Urban density improves, so people live closer to jobs.
- Mass transit becomes more viable and competitive.
- Total vehicle miles drop, cutting carbon at the source.

This isn’t a fantasy. Paris is reclaiming roads from cars and turning them into greenways. San Francisco tore down parts of its freeway system — and saw traffic decrease.

It’s Time for LA to Lead

Los Angeles has a chance to show the country what smart urban planning looks like. We don’t need more lanes on the 405. We need housing near jobs. We need walkable neighborhoods. We need serious investment in public transit, not endless expansions of freeways that only lock us deeper into car dependence.

Widening roads is easy. It’s also lazy. The hard — and smarter — path is to reimagine how we move and where we live.

Let’s stop building our way into more traffic and more emissions. Let’s start planning a city that actually works.

Sources

1.      1. UC Davis Institute of Transportation Studies (Duranton & Turner). ‘The Fundamental Law of Road Congestion.’

2.      2. Texas A&M Transportation Institute: ‘2019 Urban Mobility Report.’

3.      3. NRDC: ‘The Problem with Widening Highways’ (https://www.nrdc.org/stories/problem-widening-highways)

4.      4. Vox: ‘Why building more highways doesn’t fix traffic’ (https://www.vox.com/2014/10/28/7076365/traffic-congestion-induced-demand)

5.      5. Streetsblog USA: ‘Katy Freeway Expansion Made Traffic Worse’ (https://usa.streetsblog.org/2015/08/27/houstons-2-8-billion-freeway-widening-project-made-traffic-worse/)

6.      6. Bloomberg: ‘Paris Plans to Remove Half of Its Parking Spots’ (https://www.bloomberg.com/news/articles/2021-02-15/paris-to-remove-70-000-parking-spaces-to-reduce-car-use)

7.      7. Congress for the New Urbanism: ‘Freeways Without Futures’ report.