Interns’ Counting of Car Pools ‘More Art Than Science’ : Transportation: From their perches above the San Diego, Santa Ana and Costa Mesa freeways, non-Caltrans employees peer into vehicles to record the number of occupants.

Michael Flynn and Mary Eskander sit in a couple of folding chairs, catching the early morning sun. It’s only 6:30 a.m.--too early to seek the perfect tan.

Perched on the Von Karman Avenue bridge over the northbound San Diego Freeway near John Wayne Airport, the two college interns peer into cars as they whoosh by.

Their quarry: car-poolers.

A van with five people streaks by, but wait--a green Mercedes follows in which an overstuffed laundry bag appears to be impersonating a passenger. There’s hardly a trick the California Department of Transportation and the California Highway Patrol haven’t seen out here--from life-sized, inflated dolls to clothing store mannequins.

Once a woman even argued in court, unsuccessfully, that her unborn baby counted as a car-pool passenger.

A blue Lumina whizzes along, appearing to be an “SOV,” road-speak for the dreaded Single-Occupant Vehicle. But it’s counted as a car-pool. Someone is sprawled across the back seat, the way teen-agers talk on the phone--inverted.

Several drivers honk upon spying Flynn and Eskander in their orange vests and white hard hats up on the bridge. One raises a finger in an obscene gesture. The two interns don’t react. They’re virtually motionless, except for the tiny movements of their fingers across their one-line, bar-shaped keyboards, used to record vehicle counts.

Aspiring civil engineers from Cal State Long Beach, Flynn and Eskander are part of a small army of interns who play a key but largely unseen role in Caltrans’ $4-million “Team Rideshare” advertising blitz.

Featuring happy-tuned “Ride, ride, ride, we’re sharing a ride” television and radio commercials, the campaign urges commuters to car-pool one day a week, preferably on Thursdays, traditionally the day of heaviest traffic.

The interns’ job: Measure the success or failure of Caltrans’ costly bid to boost car-pooling every Thursday morning.

During the course of the two-hour morning vehicle count, Eskander monitors the car-pool lane while Flynn watches the regular, mixed-flow lanes, one at a time in rotation, for a total of 25 minutes each, with breaks in between. Using simple extrapolation, Caltrans figures out what the hourly car-pool numbers are for the inbound traffic (outbound traffic in the evening is more dispersed because of errand-running).

On this particular Thursday, the total number of car-pools observed is 1,789 on this stretch of the northbound San Diego Freeway, a 22% increase over the 1,465 car-pools seen at this same location on Jan. 12, the day used by Caltrans for comparison.

And while Flynn and Eskander are stationed over the San Diego Freeway, their colleagues occupy similar perches above the Santa Ana and Costa Mesa freeways, where today’s percentage increases contrasted with Jan. 12 are even better.

There are five Orange County observation posts in all, carefully spotted to catch traffic headed toward the county’s central business area from Irvine to Anaheim.

The students’ work has wide impact. Week after week, Caltrans bombards the news media with glowing statistics. They show that motorists’ use of car-pool lanes has increased dramatically--more than 44% for two recent weeks in Orange County, for example, and 27.5% when Los Angeles and Orange County results from May 27 are combined.

Caltrans has rarely reaped such a windfall in mostly positive publicity.

But Flynn, Eskander and 16 other interns at Caltrans’ Orange County office are under sharp scrutiny. Their counts are being checked and rechecked.

The Orange County results seem so hard to believe that even Caltrans didn’t accept them at first. A special team was brought in from Caltrans’ Los Angeles office to investigate whether the Orange County results were being faked.

The team’s conclusion: the counts are accurate.

Joe El-Harake, the Caltrans engineer who designs car-pool lanes and supervises the Orange County interns, secretly took readings from electronic sensors buried in each freeway lane and compared them to the interns’ vehicle counts, hour-for-hour, lane-for-lane.

“The two sets of figures closely matched,” El-Harake said. “I was relieved.”

El-Harake admits that the public may doubt Caltrans’ credibility, since there’s no independent audit of the car-pool counts by non-Caltrans employees. And he admits that the interns may censor themselves in order to please the agency that might offer them full-time jobs some day or an important letter of recommendation.

The problem with the car-pool counts, says El-Harake, is that they are “more art than science.”

“They’re too exact,” he says, “and they’re being used as if it’s a precise phenomenon. But we are only collecting data. There’s no analysis.”

To be thoroughly accurate, El-Harake says, Caltrans should conduct detailed surveys by mail of motorists whose license plates are videotaped as part of so-called origin and destination studies. But each survey can cost $500,000 or more, so they’re rarely done at all.

Controversies about the effectiveness of the program do not bother the Caltrans interns. Neither does the drudgery of counting fume-spewing trucks and cars.

“You can’t be a traffic engineer without doing traffic counts,” Eskander explained. “We have to think of it as a useful engineering job.”

The students said weather--and exhaust fumes--are the worst part of the work. “You have to be tough,” Eskander said.

Paid about $10 an hour, the interns said they have to be accurate or they won’t be considered for scarce, full-time jobs later.

Looking straight down into an approaching windshield yields little information. So Flynn and Eskander perch themselves off to one side, to get a side view.

Still, Eskander admits that that some vehicle counts are imprecise.

“Some cars or vans have dark tints on their window glass, and that makes it hard,” Eskander said. “You have to be good enough and experienced enough to make a judgment about that vehicle.

“It’s instinct sometimes. It’s a judgment call.”