Traffic

TxDOT says its strategies to reduce road congestion are working. Some experts disagree.

While TxDOT celebrates lower levels of road congestion than pre pandemic metrics, critics call the study’s methodology into question.

I-45 Traffic
Gail Delaughter/Houston Public Media
Drivers sit in traffic on I-45 northbound at North Main Street.

Harris County has six of the 10 most congested roadways in the state, according to a new report from the Texas A&M Transportation Institute. Houston's West Loop ranks number one for the second consecutive year, followed by the Eastex Freeway.

The report contends that, while road congestion is up from 2021, it still has not reached pre-pandemic levels, and as a result, Texan commuters reaped nearly $3 billion in time and cost savings in 2022.

"When you look statewide, we're back at our pre-pandemic travel levels, but we're not back at our congestion levels, which says that movement is happening more efficiently out on our transportation system," said David Schrank, a senior researcher at the Texas A&M Transportation Institute. "However, we're likely to see that congestion continue to grow because we're expecting to continue to see population growth in Texas over the next 10 to 20 years."

MORE: Dr. Schrank discusses the report on Houston Matters

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The Texas Department of Transportation points to the report as evidence its efforts to decrease congestion through road construction and expansion have been effective.

"It's encouraging to see the impact our work is having on Texas roads throughout the state to help ease congestion," TxDOT Executive Director Marc Williams said in a statement. "But our work isn't done. As more and more people move to Texas, we need to keep moving forward with projects that address traffic congestion and improve safety in areas that need it most."

However, the institute's yearly Urban Mobility Report has been criticized by transportation industry experts around the country, who have called its methodology into question.

"Outside of Texas, the Urban Mobility Report is one of the most heavily criticized pieces of urban planning because of issues like a lack of peer review and obscure methodology," said Harrison Humphreys, a policy coordinator with environmental nonprofit Air Alliance Houston. "We can apply metrics to try to understand how much road congestion costs, but there are a lot of issues with how TxDOT and TTI go about calculating those costs."

Namely, the report uses a different baseline speed than most others like it for calculating congestion. While most other congestion studies assume a relatively conservative baseline speed, TTI uses the speed at which vehicles are traveling when there is no congestion whatsoever, which oftentimes is even higher than the legal speed limit in the area. Therefore, within TTI's model, a vehicle traveling the speed limit could count as congesting the roadway. Humphreys said this can inflate the estimated cost of congestion.

Beyond controversial cost calculations, however, Humphreys argues road expansion alone has not proven to be a lasting solution for road congestion.

He says part of the problem is TxDOT, and the study itself, doesn't consider what's called "induced demand" when thinking about road expansion. That is, when roads are expanded, even more people will use them than before, causing road congestion to eventually increase again even after an initial decrease. In short, if you build it, they will come. Humphreys cites TxDOT's Katy Freeway expansion project completed in 2008 as an example.

"TxDOT implemented their philosophy to a tee. They said, ‘We'll expand the roadway. We'll make greater capacity for cars, and that will reduce the congestion,'" he said. "Five years out from that project being completed, congestion levels were at a higher rate than even prior to the project."

The Katy Freeway currently has 13 lanes at its widest point, and segments of the freeway currently sit at 7th and 16th for the most congested portions of roadway in the state.

A lasting solution to congestion, Humphreys says, is creating a more viable, expansive network of multimodal transportation options, in order to decrease the number of cars on the road in the first place.

"If we can improve the accessibility of public transit or fix our land use issues so that riding a bike to and from work is a more feasible option, all of that would reduce traffic congestion because you'd be taking cars off the road," said Humphreys.

Reducing the number of cars on the road would also further Houston's goal of decreasing transportation-related greenhouse gas emissions, as is laid out in its Climate Action Plan.

Currently, transportation accounts for 47 percent of the Houston region's total greenhouse gas emissions, far exceeding the nation's average of 29 percent.

"We must decrease the amount we drive if we want to come anywhere near reaching our climate goals," said Humphreys. "TxDOT's chosen strategy for solving a lot of our transportation issues, which is just continuously adding capacity for more cars, has hugely negative long-term climate impacts."