Variable speed limits may be coming to Texas. Could they have prevented deadly 2021 crash?
Variable speed limit signs could have helped in the February 2021 pileup crash on Interstate 35W in which six people were killed, according to a new report from the National Transportation Safety Board.
Six were killed in the 133-vehicle pileup on an icy patch of southbound TEXPress lanes near Northside Drive in Fort Worth. The National Transportation Safety Board in a preliminary report released in April found the lanes had been treated for ice with a brine solution 44 hours before the crash. The incident occurred around 6 a.m. on Feb. 11, 2021.
The NTSB is recommending Texas install variable speed limit signs on highways, but what exactly do these signs do? Here’s what to know:
What is a variable speed limit sign?
Variable speed limit signs are electronic signs located over highways that update speeds for drivers.
Essentially, these signs are speed limit markers that can update in real-time with data from highway sensors. These signs are designed to provide updated speed limits quickly in response to crashes, congestion or weather, according to the U.S. Department of Transportation’s Federal Highway Administration.
Typically in normal weather conditions, drivers are determining their operating speeds based on traffic flow and how other drivers are moving. However, if ideal conditions do not exist, drivers have to make their own decision on their speed with little information of what’s in front of them.
“Providing variable speeds limits (VSLs) capable of adapting to changing circumstances could reduce crash frequency and severity,” according to the Federal Highway Administration.
How do variable speed limit signs help?
Variable speed limit signs help by providing information in advance of slowdowns, lane closures, weather conditions, or to slow faster moving traffic.
The Federal Highway Administration puts it bluntly that humans are unlikely to survive high-speed crashes and variable speed limit signs can greatly reduce speed. These signs help in three main ways: improving visibility, providing additional time for drivers and reducing impact forces.
Some more factors tied to variable speed limit signs include:
Helping mitigate rear-end, sideswipe and other crashes on high-speed roadways.
The signs are effective on urban and rural freeways with speed limits greater than 40 mph.
Can be applied to entire roadways segments or individual lanes.
Does Texas have variable speed limit signs?
No, but they could be coming soon if House Bill 1885 is passed in the current Texas Legislative session. If passed, the bill reads:
“The commission by rule may establish a variable speed limit program to allow the temporary lowering of a prima facie speed limit to address inclement weather, congestion, road construction, or any other condition that affects the safe and orderly movement of traffic on a roadway for which the commission has the authority to establish a speed limit.”
If passed, the variable speed limit signs would take shape in either a stationary or portable device. Texas would join over a dozen states who already have variable speed limit signs on roadways.
