New data indicates no significant speed increases on urban interstates

SALT LAKE CITY — According to new data from the Utah Department of Transportation, average speeds on urban interstates along the Wasatch Front have stayed consistent, despite moving the speed limit from 65 to 70 in December 2014.

UDOT looked at average speeds for January, February and March and compared them with June 2014, prior to the speed limit increase.

The highest increase in any section appears to be 2 mph. But overall, speeds have either remained the same or even decreased since the change.

A new 70 mph speed limit sign waits to be installed.

A new 70 mph speed limit sign waits to be installed in December 2014

The initial data is in line with our expectations. We didn’t anticipate much of a change in traveling speed, considering the vast majority of the traveling public was already traveling 70 mph or above.

“People drive the speeds at which they are comfortable,” UDOT Public Information Officer John Gleason said. “We want to set the appropriate speed limit and have it reflect the speeds at which motorists are actually driving.”

Gleason also added that the intent of the speed limit increase is to create a uniform traffic flow and to minimize some of the speed differentials that can sometimes cause crashes.

While three months is a short window to make any determinations (we typically like to look at trends over several years), this data gives us an initial look at those areas where the speeds were raised.

“UDOT will continue to monitor these sections of urban interstate,” Gleason said.  “And while we don’t anticipate any changes, we want to address any potential issues as they happen.”

You can look at the data yourself on our .pdf

Speed_Study_Difference Map