Aiming to fight worsening traffic congestion on San Diego’s roads, city officials have created a $163 million master plan to install modern stoplight timing systems and other advanced technologies that combat gridlock.

The master plan, the first of its kind in city history, comes as many neighborhoods are bracing for more dense developments to absorb the region’s growing population.

In addition, recent analysis by the San Diego Association of Governments shows that the number of vehicles on the road has nearly returned to where it was before the Great Recession prompted a sharp drop beginning in 2008.

City officials said using technology to boost traffic flow is much less expensive than widening roads or building transit lines, and those solutions typically face environmental hurdles and community backlash.


The 10-year plan would connect each of the city’s 1,540 stoplights into a timing and coordination network controlled by a central hub.

It would also replace outdated technology in the isolated stoplight timing systems that San Diego has been using in various neighborhoods for the last 30 years. Many of those systems use old-fashioned modems, which will be replaced by Ethernet devices, said Duncan Hughes, a city traffic engineer.

“You can think of the existing system as using dial-up Internet, rather than today’s digital cable modems, wireless routers and fibre-optic lines,” Hughes told the City Council’s Infrastructure Committee last month. “As well as being functionally obsolete, portions of the communications network have been damaged and there are many gaps in the system.”

The first phase of the plan is repairing damaged stoplights and communication devices, which is expected to take about three years. The areas with the most damaged stoplights are Kearny Mesa, where city staff deemed 72 of 102 stoplights “deficient,” and Pacific Beach, where staff found 71 of 82 stoplights deficient.


City officials said, however, that the first phase will also include installing advanced timing systems and traffic flow upgrades in a few of the city’s most notorious areas for traffic congestion.

Upgraded timing systems and better communication between stoplights are slated to be installed in parts of Pacific Beach, Balboa Avenue in Clairemont and on University Avenue in North Park and Hillcrest.

And adaptive signal timing, described by the city as cutting edge technology, is slated for La Jolla Parkway, Rosecrans Street and the western end of Mira Mesa Boulevard.

Adaptive systems can adjust the timing of green and red lights based on unpredictable events that have suddenly altered traffic flow, such as patrons from a sold-out movie flowing from a theater after the show.


When one stoplight sees an unusually large volume of cars, it immediately relays that information to each stoplight downstream in the series. That allows those stoplights to stay green for longer than they usually would at that time of day.

A city experiment with adaptive signals that began last year on Sorrento Valley’s Lusk Boulevard has been deemed a success, Hughes said.

The master plan also calls for installing cameras in many places, which will help the city monitor traffic and also count pedestrians and bicyclists to see whether city efforts to encourage those commuting options are working.

The city recently launched a pilot project with five cameras on Harbor Drive near San Diego International Airport, which officials say has allowed them to make left-arrow green lights off of Harbor last longer when traffic flowing out of the airport increases.


Hughes said the plan would put San Diego in a much stronger position to analyze and improve traffic flow.

“The proposed system will enable the city to manage, maintain and measure the performance of our streets,” he said.

City officials said they plan to pay for the upgrades with a variety or funding sources, including grants, developer mitigation for projects and revenue from Transnet, the county’s half-cent sales tax surcharge for transportation projects.