Caltrans to conduct six-week study on Vista highway

VISTA, Calif. —¬†¬†Caltrans is undertaking a six-week experiment on eastbound state Route 78 in Vista to study whether getting motorists to slow down could actually speed up their commute.

Caltrans San Diego crews have placed seven electronic speed signs on eastbound SR-78 between Vista Village Drive and Interstate 15. During commute hours, the speed signs will advise travelers of speeds that will optimize their commute time, even though those signs will show optimal speeds below the speed limit, according to Caltrans officials.

“The aim of synchronizing traffic is to gradually slow traffic in advance of a bottleneck in order to keep traffic moving and avoiding stop-and- go traffic,” said Allan Kosup, the director of the SR-78 corridor project. “Essentially we are asking motorists to slow down to go faster.”

The electronic speed signs will display advisory speeds — always in increments of 5 mph — that are not enforceable by law, but that act as an advisory for the best way to avoid traffic jams, Caltrans officials said.

The study is being completed by Caltrans in partnership with the Institute of Transportation Studies and UC Berkeley’s Partnership for Advanced Transportation Technology.

“At the completion of the six weeks, staff from UC Berkeley will verify the algorithms (and) assess the compliance rates and overall change in queuing on one of San Diego (County’s) most congested interchanges,” said Karen Jewel, project manager for Caltrans’ SR-76/SR-78 corridor project. “Interested parties … can expect to view the study’s findings later this summer.”

Those interested can also follow the study’s real-time results at http://www.caconnectedvehicletestbed.org/VSA/.