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Casey Christie / The Californian

A traffic light on the southbound on ramp at Olive Drive will eventually regulate traffic flow onto Highway 99 here is currently facing west instead of north.

A facet of big(ger) city life is coming to Bakersfield freeway on-ramps.


We're talking about ramp meters, the addition of green-and-red lights that tell drivers when they can and can't merge onto the freeway, a common sight in Southern California and Fresno but not in this part of the valley.

One is being constructed as part of the county of Kern's expansion of an Olive Drive southbound Highway 99 on-ramp in north Bakersfield, though it won't actually be turned on until more are installed throughout the 99 corridor through town.

And those aren't going in anytime soon because there's no money for them now, said John Liu, deputy district director of Caltrans District 6 maintenance and operations, which includes Bakersfield.

For the uninitiated, meters are used to regulate the rate at which cars enter freeways. Transportation officials say they delay traffic at the meter but speed it up on the freeway.

A December 2011 Caltrans ramp meter plan looking at needs over the next decade says they prevent or delay the onset of congestion, eliminate the entry of large groups, or "platoons," of vehicles and improve overall speeds of traffic.

"A lot of times people think the only purpose of them is to prevent people from getting on the freeway, but that's not the case," Liu said.

Kern County Roads Director Craig Pope, however, worries that the Olive Drive ramp meter will jam up traffic on Olive Drive -- relieving a freeway problem for Caltrans but creating a street one for the county.

Caltrans required the county to put in the meter as a condition of granting it a permit to make the interchange improvements in what is Caltrans right-of-way. (It's going in at the bottom of the Olive on-ramp that's on the west side of 99.)

The county tried to talk Caltrans out of requiring the meter but failed, Pope said.

"They said, 'You want a permit?'" he said.

But a couple things should mitigate the problems on Olive Drive, Pope said.

First off, he guessed, the meter probably won't be turned on for five or 10 years since the county successfully argued that it wouldn't do much good if the rest of Bakersfield's 99 corridor is meter-free.

And the county's $3 million on-ramp project includes an auxiliary lane that takes traffic directly from there to the Highway 204 on-ramp, meaning drivers won't have to merge onto 99 before taking the 204 exit to central Bakersfield, Pope said.

He said that should keep traffic moving both on the on-ramp and on Highway 99.

"The auxiliary lane will be a huge improvement," Pope said.

District 6 -- which includes the counties of Fresno, Kern, Kings, Madera and Tulare -- had 60 existing and 134 planned ramp meters at the time of the 2011 Caltrans ramp metering plan.

The routes with current or planned metering in the district were State Routes 41, 58, 99, 168, 178, 180 and 198, it says.

"District 6 has considerable congestion during traffic incidents and winter 'Tule' fog conditions. The fog causes visibility issues and occasional major accidents, both (of) which cause traffic delays," the Caltrans report says. "Also, the state highway serves as a 'main street' within the city limits of a number of small communities. This can present occasional congestion issues due to busy city traffic.

"With increasing population in the valley cities, more extensive congestion issues are anticipated."

Ramp metering has been around in California since the 1960s, according to Caltrans' 2011 report. There then were about 2,460 meters statewide, accounting for more than 60 percent of those in the United States.

It quotes a slew of studies touting the benefits of meters, including one by the Minnesota Department of Transportation in 2001 that evaluated traffic flow and safety impacts of ramp metering by turning off all 430 ramp meters in the Minneapolis/St. Paul area for six weeks.

It found that when the meters were off, freeway traffic volumes dropped 9 percent; travel times increased by 22 percent; speeds decreased by 7 percent; and the number of crashes increased by 26 percent.

The Caltrans report also refers to a story in the San Francisco Chronicle from early 2008 that looked at what happened when Caltrans activated metering lights on seven eastbound on-ramps of I-580 from 2:30 to 7:30 p.m. Monday through Friday in January of that year.

The paper quoted Caltrans as saying freeway travel times fell between 15 and 45 percent, depending on time and day.

"It seems like even though a lot of us may not like these things, they are working," Caltrans spokesman Michael Lopez told The Chronicle.