Modern cars are faster, more fuel-efficient, safer and more nimble than their counterparts of decades past, yet modern highway speed limits fail to take this into consideration.

Given the poor condition of many U.S. highways, combined with the distracted drivers using them (and the general ignorance of vehicle maintenance), perhaps that isn’t a bad thing.  Many drivers aren’t capable of dealing with emergencies at current posted speeds, so raising speed limits without other associated changes could prove to be a very bad idea.

We may be about to find out. As News Radio WOAI explains, the Texas Department of Transportation (TDOT) is proposing an 85 mile per hour speed limit for a new toll road stretching from San Antonio through Austin. The road, State Highway 130, would be the first in the United States posted with a limit of 85 miles per hour.

Texas and Utah both have roads posted at 80 mph, so adding another five miles per hour to a newly-constructed highway isn’t that much of a stretch. Besides, as the speed management director for the TDOT, Darren McDaniel, explains, the road “was designed under extremely high design parameters.”

Since the toll road is meant to ease traffic on Interstate 35, it’s hoped the higher speed and lower traffic density will appeal to motorists willing to pay for the convenience of an expedited trip. It’s not a done deal yet, either, since the next step is a speed study from the TDOT. If the road is deemed safe, then an 85 mph limit is likely.

As expected, critics have already said the higher limits will lead to more traffic fatalities, but McDaniel is quick to point out that the safest roads are those with vehicles traveling at or near a common speed. In other words, speed isn’t necessarily dangerous, but a significant difference in speed among vehicles is.