Houston traffic is horrible and about to get a lot worse (unless we do this)

15 recommended upgrades to Houston highways Houston is the fastest-growing city in the nation, and all those people bring lots of cars to cram onto the roadways. One research group has prioritized 15 upgrade projects to ease Houston traffic.

See what they are... less 15 recommended upgrades to Houston highways Houston is the fastest-growing city in the nation, and all those people bring lots of cars to cram onto the roadways. One research group has prioritized 15 upgrade ... more Photo: Cody Duty, Houston Chronicle Photo: Cody Duty, Houston Chronicle Image 1 of / 48 Caption Close Houston traffic is horrible and about to get a lot worse (unless we do this) 1 / 48 Back to Gallery

Texas' population grew by almost 60 percent since 1990, adding 10 million residents at the fastest rate in the nation. All those new folks bring their automobiles, and day after day we're trying to cram more and more cars onto our roadways, bringing traffic through important arteries of commerce to a near standstill daily.

But looking ahead, things could get even worse. The state demographer projected Texas population will double by 2050—so are we prepared to double the capacity of our transportation infrastructure, or will our cities stall in unbreakable gridlock? One research group is sounding the alarm.

"The current highway system is already inadequate," said Carolyn Kelly, co-author of a recent report on the Texas highway system. "Texas will need massive upgrade projects, otherwise you could be looking at a transportation system that's increasingly congested and doesn't support the growth of the state."

Kelly and others worked on behalf of TRIP, a national transportation research group, to mine data from the Texas Department of Transportation and produce a prioritized list of major upgrade projects in major cities across the Lone Star State. The project plans belong to TXDOT, but the priorities are the work of TRIP, based on how badly improvements are needed and how easily improvements could be implemented.

Houston has an exceptionally deep reliance on its roadways; past research by the Center for Houston's Future found that the city's population swells by over 30 percent daily, as about 600,000 people drive into the city for work every day. Almost half of city workers spend more than an hour commuting each day.

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Research abounds with insight into the detrimental effects of traffic congestion. It stalls business efficiency, elongating transport times for goods and forcing workers to spend more time being idle and unproductive behind the wheel.

It also induces anxiety, a feeling that can take years off of commuters' lives when experienced on a daily basis. Tiny cancer-causing particles wafting out of exhaust pipes make their ways into commuters' lungs amidst regular gridlocks of thousands of vehicles. The general air quality also suffers; more traffic means each vehicle spends more time on the road, spewing noxious fumes into the city ambiance.

TRIP recommended 100 upgrade projects for Texas and 15 for Houston, but they come with a hefty price tag. The group's most highly-recommended work for Houston, an expansion of Interstate 45 from the city's center to near its southern edge, is priced at $6.7 billion. To put that in perspective, statewide voters passed a $1.7 billion transportation spending plan to upgrade infrastructure.

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"These projects and many others will remain standing on the drawing board unless Texas can provide added transportation funding at the state and local levels," Kelly said.

She said improving roadways alone won't be enough to stem Texas' mounting transportation problems, and a well-balanced approach will include upgrades to public transportation. Significant efforts currently in the works include high-speed rails lines linking Dallas and Houston and San Antonio and Austin (which Forbes ranked the nation's 4th-most congested city in 2014).

But the TRIP focused exclusively on highways, not public transportation.

Check out our slideshow to see the 15 top recommended upgrade projects to Houston highways.