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Caltrans InfoEdge

Caltrans News Release

District 11

Dec. 19, 2016

Contact: Hayden Manning (Caltrans) , (619) 688-6670

Smart Highway Signs Improve Safety and Mobility For Commuters and Shoppers

SAN DIEGO.—Caltrans has placed a total of six Smart Portable Changeable Messages Signs (PCMS) along Interstate 8, Interstate 805 and State Route 163 (SR-163) in the Mission Valley area to alert motorists about slowing traffic.  During the holiday season, traffic near Mission Valley freeways increases.  Smart PCMS can be remotely programmed with messages that change as traffic conditions change. Cellular technology allows the signs to communicate with each other.
When highway speeds drop below 45 MPH the signs will activate the message “SLOWING AHEAD PREPARE TO STOP.”  At speeds below 35 MPH, the message will read “STOPPED TRAFFIC AHEAD.”  The signs go dark with a dot in each corner when highway speeds exceed 45 MPH.

Smart PCMS are safer for highway workers than standard Changeable Message Signs because they eliminate the need for onsite programming, including turning the signs on or off.  The signs can be placed at locations where traffic engineers believe a specific message is needed at a particular time. 

“The Smart PCMS were placed the week of Thanksgiving and have annually been in use since 2012 for the Labor Day Holiday, summer events at the Del Mar Fairgrounds, and during the recent construction at Otay Mesa,” said Caltrans Traffic Engineer Fred Abdipour.  “We saw a 35 percent drop in rear end collisions the first three years the signs were placed.”

Motorists will see these signs in spring 2017 for the SR-163 Friars Road Improvement Project. 

Follow @SDCaltrans on Twitter at and visit Caltrans District 11 on Facebook at for up-to-date news and traffic information related to state highways in San Diego and Imperial counties.

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