Mark Wetzel, Deseret News
Travelers on Interstate 80 through Parley’s Canyon are seeing new electronic speed limit signs whose readings can change according to driving conditions.

Travelers on Interstate 80 through Parley’s Canyon are seeing new electronic speed limit signs whose readings can change according to driving conditions — an application of technology that might surprise or confuse some drivers, but will no doubt improve safety.

A large number of bad weather accidents are attributed to the practice formally described by police as driving “too fast for existing conditions.” With the new variable speed limit signs posted by the Utah Department of Transportation, the appropriate pace of travel on ice-covered or snow-packed pavement won’t be left up to the judgment of individual drivers.

While most commuters exercise common sense when the weather turns nasty, not everyone is so inclined. It’s not uncommon during such conditions to see some drivers proceeding cautiously while others bound along as if the roads are dry and visibility clear. A stretch of freeway where vehicles are traveling at widely diverging speeds is a dangerous place indeed.

UDOT is spending more than $700,000 to implement the new signage, and that is a relatively small investment given the likely returns in money saved by reducing accident rates. But that, of course, will depend on how strictly the variable limits are enforced.

In other words, signage that drops the speed limit by as much as 40 mph must be viewed as something more than a polite suggestion. It’s up to the Utah Highway Patrol and other law enforcement agencies to make sure the new systems have the desired impact.

Assuming the state sees the expected results, UDOT should work to expand the program. The agency says it is already contemplating implementation in other areas prone to hazardous conditions, like Sardine Canyon in Cache County, or on I-15 at the Point of the Mountain.

It would not be surprising – and would be quite gratifying – to see this concept of “smart highways” eventually spread to all thoroughfares where traffic backs up regardless of weather. The state of Washington has been a pioneer in this arena, using variable speed limits on congested roadways to better manage overall traffic flow.

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The investment of tax dollars in this kind of technology is money well spent. UDOT earns credit for pushing the concept, and for its increasing use of other technology to improve traffic conditions. UDOT says its system for timing traffic lights, for example, has resulted in more efficient travel on roads where busy intersections tend to clog up during rush hour.

That system, however, is currently of benefit only to those traveling on roads managed by the state. On city and county roads, in many jurisdictions, motorists may find the timing of semaphores less logical and an actual impediment to efficient travel.

Overall, we are seeing the advent of technology that can have immediate and dramatic impact on travel safety and efficiency. It would be nice if there were no limits on the speed at which this innovation might spread.