The Colorado Department of Transportation, in coordination with the Colorado State Patrol, and Silverthorne Police Department, will pace vehicles on I-70 in an effort to reduce congestion using a technique sometimes called "rolling roadblocks."


The new method is aimed at reducing congestion and accidents and will take place on eastbound Interstate 70 from Silverthorne to the Eisenhower/Johnson Memorial Tunnel.

Beginning at 10 a.m. on Saturday, August 13, a single CSP or SPD car will switch on its emergency lights and merge ahead of traffic, starting just east of the Silverthorne Interchange. The police vehicle will use the center lane to pace eastbound vehicles, at speeds between 45 and 55 mph, to the entrance of the EJMT.

Pacing operations will repeat about every 10 minutes, until around 4 p.m.

Saturday's test will help determine the feasibility of pacing vehicles during heavier traffic periods in July and August and winter weekends during the ski season.

Information, including traffic counts, speeds and flows, will be collected and analyzed to determine if the initial test enhanced safety and traffic flow. If the data is favorable, another test will be put into operation on the segment from Silverthorne to Empire in late September.

"The primary purpose of testing Rolling Speed Harmonization is to improve traffic flow and see if it's possible to eliminate metering at the tunnel," says CDOT Regional Transportation Director Tony DeVito. "If we can keep traffic flowing evenly at a safe speed through the corridor during our heavier traffic periods, we can keep I-70 from the gridlock that creates the need to meter."

CDOT holds or "meters" eastbound traffic at the tunnel when vehicle volumes exceed the capacity of I-70. When back-ups occur, CDOT stops vehicles from entering the tunnel, allowing traffic to clear, before releasing more traffic into the tunnel.

"It's not just about eliminating the need to meter, it's also about the safety of the traveling public," adds DeVito. "As traffic volumes increase, the differentials in speed among vehicles increase the possibility of traffic accidents and accidents contribute to the congestion problem. It's a vicious circle."

Similar speed control operations, often known as "rolling roadblocks," have been effectively used in other states, such as Florida, Nebraska and Virginia, to safely move vehicles through heavy traffic areas or construction zones.

After Rolling Speed Harmonization is tested for its effectiveness in dry conditions, CDOT, CSP and SPD will test its use again at the end of the year, during winter driving conditions.