Stock picture.

There have been howls of protest from across the transport spectrum at the Texas transportation commission's decision to approve the highest speed limit in the United States on a privately-run toll road.

Drivers will be allowed to cruise at 85 miles per hour (137km/h) along a new 67km stretch of State Highway 130 between Austin and San Antonio on the Mexican border, which is due to open in November, several kilometres east of the increasingly crowded Interstate 35.

The maximum speed limit on highways in most of the United States is either 70mph (112km/h) or 75mph (120km/h), although there are some long, straight stretches in rural West Texas and Utah with 80mph (128km/h) speed limits. There are no longer any roads in the US with no speed limit.

So how did they get it right?

The SH 130 Concession Company, a joint venture of Zachry American Infrastructure and Spanish private toll roads specialist Cintra -itself controlled by Ferrovial - promised to pay the Texas department of transportation an extra $65 million (R532 million) if it permitted an 80mph (128km/h) limit, and $100 million (R818 million) if it allowed an 85mph (137km/h) limit.

Austin resident Alan Guckian said he'd love it.

“Sometimes it's fun to just open it up.”

He said many drivers would be attracted by the higher speed limit but, for most, it wouldn't be worth the cost - even though the company hasn't announced yet how much the toll will be for the new section.

“For most people I talk to,” he said, “it's a cost issue.”

But Steve Marcy, who uses another section of the toll road to commute from his home north of Austin to his job in San Antonio, said that although he'd be comfortable driving at 137km/h, he'd be worried about other drivers whose vehicles weren't in good condition.

“A tyre blowout at 85 could be a big problem.”

Insurance Institute for Highway Safety spokesman Russ Rader said: “The research is clear that when speed limits go up, fatalities go up.”

He said higher speed limits get people to their destinations faster, “but the trade-off is more crashes and more highway deaths.”

Due to congestion on Interstate 35 the new road is expected to carry a large amount of commercial traffic between to and from Mexico, but even the truckers are complaining about the 137km/h speed limit.

American Trucking Associations president Bill Graves said: “On today's busy and congested highways, it is simply unfathomable that a state would allow drivers to put themselves and others at risk by increasing speed limits to such excessive heights.”

Graves said the state was increasing the danger to the public as it sought to get more traffic and earn more money for the toll operators by “giving motorists carte blanche to put the pedal to the metal.” - AFP