On one brand new stretch of toll road southeast of Austin, Texas, you can cruise at 85 mph and not worry about being pulled over for speeding.

That’s because starting Wednesday, on this 41-mile segment of road, 85 mph is the legal speed limit. It’s the highest in the country, and some are wondering whether it might be a little too high.

The new section of toll road provides an alternative to I-35, the congested artery that’s the spine of the Texas highway system. People who have driven between San Antonio and Austin can attest to the traffic -- it can be bumper to bumper. In addition to long haul truckers headed from the border to the interior of the U.S. and back, there are also soccer moms hopping on and off to get to Walmart and thousands of suburban commuters headed into the office.

So an alternate highway makes sense, but why 85 mph? Clearly drivers want to get where they’re going faster, and at 85 mph, the new toll road potentially cuts the drive time from Austin to San Antonio in half.

The Texas Department of Transportation says although it’s fast, the new speed limit is safe. The road was designed for it. It’s straight and through rural areas. But critics point out the Transportation Department had a financial incentive to set the speed higher.

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As part of its contract with SH130 Concession Co., the company funding the new toll road, the state would receive $67 million for setting the speed limit at 80 mph and $100 million if the speed was 85 mph. Even so, Chris Lippincott, a spokesman for the company, said, “Drivers retain the ultimate responsibility for safety.”

The high speed has some concerned. Groups like the Governors Highway Safety Association point out that as speeds go up, so do fatalities.

“Speeding is a big issue where we are not making progress,” the association's Jonathan Adkins said. He said although seatbelt use is up and drunken driving is down, deaths due to speeding continue to climb. In fact, he said, 13,000 traffic deaths each year are due to speeding.

And what about the tendency to drive five to 10 miles over any posted speed limit? Does that mean cars really will be cruising closer to 100 mph?

The company points out that the state can revise its posted speed limits at any time if it turns out 85 mph is, in fact, too fast. Officers will be patrolling the new road, and Texas law enforcement sources say although it’s up to each individual officer, they can ticket drivers for going just a mile over the speed limit.

There also might be a financial consideration for drivers to stay under 85 mph. The Department of Energy estimates that for each 5 mph you go over 50 mph, you pay about a quarter extra a gallon in lost fuel efficiency.