SURFING AROUND GRIDLOCK TRAFFIC GUIDE'S NET EFFECT? TIME SAVED.

Byline: Dana Bartholomew Staff Writer

The nation's first Web-based traffic seer will soon enable Los Angeles motorists to accurately predict - and avoid - congestion up to an hour before it occurs, its makers claim.

The free Internet site, created by a team of scientists from the University of California at Berkeley, will give motorists an instant bead on freeway logjams and will tell them how long they'll be in their car.

The Freeway Performance Evaluation Monitoring System, or PeMS, will be accessible via home or office computer, Palm Pilot or Web-capable cellular phone. Yes, even from car phones.

``It's exciting,'' said Tom Choe, Caltrans chief for the Office of Freeway Operations. ``We haven't seen anything of its type before.''

The PeMS system is expected to debut in the Los Angeles Basin before the end of February, in San Bernardino by the end of March and in the Bay Area as soon as technical bumps are smoothed over.

``The chief benefit is you can adjust your trip times to avoid a traffic jam,'' said Pravin Varaiya, a Berkeley computer science and electrical engineering professor, who invented PeMS with his students using California Department of Transportation road sensors, software and money.

``But if you're in a traffic jam already, it'll tell you how long you'll be in traffic. We can't get you there faster, but at least you'll know how long it'll take.''

Goodbye radio traffic updates, hello point-and-click traffic conditions.

With a click on a map at the beginning of a journey and a click at the end, the PeMS will instantly predict traffic times and offer sensible alternate routes. Such routes can then be programmed for easy future reference.

Berkeley researchers chose the Los Angeles region to showcase their system because area Caltrans officials were receptive and because the city's highways have the most sophisticated network of under-road ``loop detector'' sensors in the state.

The PeMS system, first tested in Orange County, has been used by traffic engineers from Caltrans' Los Angeles-Ventura office for several months to watch, predict and control freeway traffic performance through on-ramp metering.

The UC Berkeley system, paid for by a $500,000 grant from Caltrans, uses Caltrans roadway sensors to count cars and trucks.

The information is then fed into a Caltrans Advanced Transportation Monitoring System, which transmits it twice a minute via high-speed cable from Los Angeles to UC Berkeley's Computer and Electrical Engineering Department.

Berkeley's PeMS software, using historic traffic data, then crunches the Caltrans numbers into charts, graphs and tables to map out real-time traffic and to predict future conditions.

PeMS traffic information is then available through the Internet.

Though some Web sites already post current traffic conditions using Caltrans data, the PeMS software will be the first to enter the murky realm of traffic and travel time prediction.

In addition to allowing Caltrans engineers to spot nasty bottlenecks on the Ventura Freeway or the speed of cars on the San Diego Freeway, it can detect faults in loop detectors throughout the region.

The result could be the most advanced traffic detection system in the country, if not the world, traffic experts say.

``We want to be cutting edge,'' Choe said. ``We want to be leaders in the state. And with the largest (Caltrans) district in the state, we have the most congestion - with 60 percent of the congestion statewide during peak hours.

``Los Angeles will be the first city to do this in the state, but it's much like the Internet,'' he added. ``Don't expect the world, initially. The system will get better and better: The idea is to save time.''

The Berkeley traffic software is currently accessible only by Caltrans officials.

Soon, however, the public will be able to register on the PeMS site, transacct.eecs.berkeley.edu.

Within five to 10 years, officials hope to wire it to Los Angeles loop detectors for the first surface street monitor and predictor in the state. Varaiya predicts $1.5 billion in fuel and motorists' time could be saved in Los Angeles with better traffic management at a rate of $20 per hour saved.

Some remain skeptical, however.

One veteran AM radio news editor pooh-poohed the PeMS system as a gimmick.

``Do you know the L.A. freeway system at all?'' asked the editor, who spoke only on the condition of anonymity. ``Predicting is bull, right out of the gate. I'm speaking from a commuter's viewpoint here, from living and dying on the L.A. freeway system.''

You can check a computer, then hit the freeway eight minutes later, he said, and conditions will be radically different. And checking any system in your car could be downright dangerous, if not deadly.

``Bottom line: radio reporters aren't going away for a long time,'' he said.

Others see it differently.

``That would be amazing,'' said West Hills resident Sabrena Valentino, 36, gassing up her car in the rain Monday, when told about the system. ``My husband and I are always on the road, and God knows how much time it takes to get home.''

Given access to free PeMS, she said, ``I'd do it.''

CAPTION(S):

photo, box

Photo: (color) FREEWAY PERFORMANCE EVALUATION MONITORING SYSTEM (PeMS)

Box: BEATING THE TRAFFIC JAM WITH PeMS

Gregg Miller/Staff Artist