An Aug. 13 test of a pacing process that keeps cars moving at a constant, but controlled speed to the Eisenhower tunnel from Silverthorne was successful, Colorado Department of Transportation officials said.
They plan to follow the test up with a longer trial run to Empire Junction later this month.
“Operationally, it went well,” CDOT spokesman Bob Wilson said.
Regional law enforcement and CDOT, agencies that partnered for the first test, will join forces again Sept. 25 to implement the longer trial pacing process from Silverthorne through the Eisenhower Tunnel to Empire Junction.
“Then what we'll do is another test in December when we have colder weather and driving conditions may be more winter-like,” Wilson said. “If all goes well, we'll start looking at possible implementation.”
The first test, conducted on a slower Saturday in the summer, allowed CDOT and law enforcement agencies to try out the pacing process, known officially as “rolling speed harmonization.” The various entities involved were able to communicate effectively and soon discovered they were able to keep traffic moving at a constant 55 miles per hour — just 5 miles per hour slower than the posted speed limit — by running patrol vehicles ahead of traffic with their lights activated in five-minute intervals from 10 a.m.-2 p.m.
The practice is intended to keep cars moving up the 10-mile incline from the Silverthorne interchange to the Eisenhower Tunnel and beyond at a slower, more constant pace, which officials hope will prevent accidents and cars getting stuck with wheels spinning on icy roads.
“The idea was we could reduce accidents that happen when there are differential speeds or uncontrolled drivers in icy conditions,” CDOT traffic engineer Bernie Guevara told the Summit Board of County Commissioners at a recent joint meeting.
The process might also reduce the need for metering at the tunnel, officials said. Often, on busy weekends when traffic gets heavy, CDOT has to stop, or meter, traffic at Eisenhower for up to 20 minutes to prevent a gridlock inside the tunnel, which would isolate cars inside and prevent emergency vehicle access.
“If it results in the benefit of less metering we're all better off,” CDOT regional director Tony DeVito said of the pacing process. “What we'd like to do is delay that congestion if at all possible.”
If the longer test of rolling speed harmonization later this month and the December test both produce positive results the program might be implemented early next year, most likely on Sunday afternoons or peak travel days and weekends such as Martin Luther King Day. Officials said specific details are still to be determined.