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Grappling with speeding, crashes

Technology at intersections, increased patrols in problem spots aimed at making local roads safer

Posted: August 5, 2012 2:00 a.m.
Updated: August 5, 2012 2:00 a.m.

On May 17, a 39-year-old motorcyclist was killed when his vehicle “T-boned” a stopped rental van at Rutherford Place and Decoro Drive.

On July 10, one man was killed and his brother remains in critical condition when the car careened off the driving lanes of Soledad Canyon Road and slammed into some trees in the center divider just west of Camp Plenty Road.

On July 29, a driver lost control of her SUV on Golden Valley Road and the vehicle hurled into a tree and a fire hydrant, with car parts crashing into a bank and leaving wreckage inside. The driver was injured but survived.

The common thread in all three crashes: Speed is believed to be a major factor.

Nationwide, speed played a role in 32 percent of all fatal crashes in 2010, according to federal numbers released last week.

Locally, the Santa Clarita Valley Sheriff’s Station’s traffic division spends much of its time trying to get people to slow down and drive more safely. A greater number of deputies are deployed to problem speeding areas or scenes of major crashes to try to get drivers to slow down, said Sgt. Richard Cohen of the traffic division.

But a less obvious deterrent to breaking the speed limit than stepped-up Sheriff’s Department patrols can be found behind a locked door on the third floor of Santa Clarita City Hall, where the city’s traffic operations center can be found.

There 176 intersections throughout the city are monitored with cameras, sensors and closed-circuit video cameras.

Signal timing is based on complex modeling that takes into account the vehicle count per hour, peak hours, directional traffic and the speed of the cars, along with other factors, said Cesar Romo, signal operations supervisor for Santa Clarita. The timing is restructured about every three years, although sometimes it’s done earlier based on calls from residents.

“We’re very aggressive in signal timing,” Romo said.

Speed is a major factor in the light timing, since the synchronization is modeled based on speed limits, Romo said.

“If you go at the speed limit and you start at a particular intersection, you shouldn’t be stopped by a red light if you’re following the speed limit,” Romo said.

Platoons of cars

Some residents may get frustrated that they have to wait at red lights for long periods of time, but Romo said that’s normal when entering a major road from a side street. It takes a few cycles to catch up with the larger groups of cars, which he calls platoons.

At larger intersections — such as McBean Parkway and Valencia Boulevard, which sees about 90,000 cars passing each day — the signal timing is two minutes and includes eight movements of left turns, right turns and through traffic, Romo said. Time must be added to that two minutes if there are pedestrians or bicyclists.”

The city traffic center uses a point-to-point system for timing, Romo said.

For example, say Point A is Bouquet Canyon Road at Newhall Ranch Road and Point B is Bouquet at Plum Canyon Road.

A platoon of cars traveling between the two points at the speed limit should encounter few or no red lights between Point A and Point B, he said.

Those who enter Bouquet between the two points, however, will hit some red lights as cars from the platoon catch up with them.

Timing signals is made more challenging by the fact that Santa Clarita is not built on a grid, like many other area cities are.

The synchronization system is not tied to the red-light cameras throughout the city, said city spokeswoman Gail Ortiz.


The county has synchronized some traffic signals with the city, said Kerjon Lee, public affairs manager with Los Angeles County Public Works.

“The county has previously worked with Santa Clarita to synchronize signals on several routes in the valley,” Lee said in an email, adding that the county has helped synchronize intersections on The Old Road, Stevenson Ranch Parkway, Pico Canyon Road and Copper Hill Drive.

The county is also planning to add new route synchronization by the end of 2012 on Lost Canyon Road, Sierra Highway, Valencia Boulevard and Magic Mountain Parkway and The Old Road.

The city is working to improve its traffic signal program and plans to update connections with an increase in fiber optic and wireless connections in 2014, Ortiz said. This will allow for better monitoring, better reporting and better timing of traffic signals.

In conjunction with other traffic improvements including construction of the cross-valley connector and lane widening, traffic flow has improved considerably over the years, Ortiz said.

“Those things have had a large impact cumulatively,” she said. “It does not take an hour to get from one end of town to the other.”



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