Daylight Use of Headlights Helps Cut Accidents

The accident rate on Santiago Canyon Road dropped 58% after a program encouraging drivers to use headlights during daylight hours was introduced, a new study shows.

Accident rates are computed on the number of accidents per million vehicle miles. The total number of accidents on the 13-mile stretch of two-lane highway between Orange and Trabuco Canyon decreased by seven in 1987 and 1988 compared to the previous two-year period, despite a more than 100% increase in the daily traffic volume, according to the study. The number of accidents dropped from 81 to 74.

No statistics were provided on the numbers of deaths and injuries.

The study is the first comparing accident trends since daytime headlight programs were implemented throughout Orange County over the past five years. Other programs are in effect on Ortega Highway and Laguna Canyon Road. While use of headlights during the day is voluntary, surveys by police and county engineers show a compliance rate of between 50% and 70%.

‘An Outstanding Program’

A county engineer who conducted the study cautioned that due to drastic changes in traffic volume and patterns, the study is not scientific.

But law enforcement officials said the findings reinforce their belief that the headlight program is succeeding in reducing accidents.

“It’s an outstanding program for our area,” said Officer Mike Lundquist, spokesman for the Santa Ana division of the California Highway Patrol. Lundquist said the 58% reduction is “probably one of the highest in the state.”

While more recent accident figures are not available, Lundquist said the trend appears to continue downward. CHP Motorcycle Officer Wally Seibert, for example, said he has noticed a decrease in accidents in his early-morning patrols of the highway.

“I think they work,” Seibert said. “It’s a visual thing. It’s like with motorcycles. Someone sees that your headlights are on and it’s easier to see the vehicle.”

Signs Posted

The state Department of Transportation posted signs asking for daytime headlights along Santiago Canyon Road in September, 1986, at the request of the CHP after 10 fatalities and 109 injuries resulted from traffic accidents there between Jan. 1, 1984, and Dec. 31, 1985. Although the roadway’s overall accident rate at the time was well below state averages, the severity of accidents was such that Capt. C. A. Lynd of the CHP’s Santa Ana division asked for the signs.

A Caltrans study at the time of 10 other headlight programs outside Orange County found that the total accident rate was reduced 18% after the posting of headlight signs.

The Santiago Canyon Road study, completed Aug. 1, found even more dramatic reductions.

James Swatzel, a county senior civil engineer who conducted the study, also documented significant reductions in types of accidents. Accidents in which vehicles were sideswiped decreased from 16 in the previous two-year period to nine in the next two-year period, the report found. The number of accidents involving overturned vehicles dropped from 16 to six over the same time periods. And accidents related to unsafe speed decreased from 25 to 19, according to the report.

Although some accident categories showed small increases, Swatzel noted that there had been such a large increase in traffic on the roadway that a net reduction in the accident rate still occurred.

Traffic Volume Doubled

The daily traffic volume doubled from 6,000 vehicles to 12,000 in one six-mile stretch of road between Silverado and Live Oak canyons, the report said. Traffic volume on the remaining seven-mile stretch between Silverado Canyon and Chapman Road increased from 11,000 vehicles daily to 16,000, the report said.

Although no similar studies have been conducted on Ortega Highway or Laguna Canyon Road, law enforcement officers there say they are also seeing accident reductions.

The signs went up in June, 1985, along a 14-mile stretch of Ortega Highway, where CHP statistics showed that there were 87 major accidents resulting in 95 injuries and four deaths during 1984. Headlight signs went up in 1984 on a five-mile stretch of Laguna Canyon Road between the San Diego Freeway and El Toro Road because of a concentration of serious accidents there.

Headlight signs “make people more aware that this is a problem area and it makes oncoming vehicles more visible,” said Laguna Beach Police Sgt. Linda Parker. “It makes them more alert.”

Cut Estimated at 25%

Use of headlight signs and a CHP radar enforcement program have combined to reduce accidents along Ortega Highway by as much as 25%, said Lt. Michael Bair of the CHP office in San Juan Capistrano.

“I think the headlight program is helping not so much for visibility but to remind drivers . . . that there is something a little unique about driving this highway,” Bair said.

As successful as the headlight programs seem to be, Swatzel warned in his report that lights should not be considered a general solution. The fact that the lights are unusual is what gets the attention of drivers, Swatzel said.

“Any proliferation of this method will render it completely ineffective,” he said.