Q As you pass Alamo going south on Interstate 680, the newly paved carpool lane has only yellow Botts' dots on the left and not a solid yellow line. There's a fairly wide shoulder and I'm pretty sure it's not legal to drive on that, but some crazy idiot was and passed me on the left. As you near San Ramon, a solid yellow line actually appears. Is this a real lane?

J.C. Belkin

Danville

A It's not -- yet. In a few weeks Caltrans will begin building an auxiliary lane between Sycamore Valley Road and Crow Canyon Road that will require that existing lines be removed when lanes are shifted toward the median.

Interstate 880 in San Leandro
Interstate 880 in San Leandro

When final striping of the I-680 paving project was being done a few months ago, construction bosses decided not to add the yellow striping to avoid unnecessary scarring of the new pavement when lanes are shifted toward the center of the freeway. So temporary Botts' dots were installed and the yellow striping will come later.

Q Looks like they're gearing up for some major construction near Davis Street at Interstate 880. What's the plan?

John Hamblin

Walnut Creek

A Caltrans is adding a carpool lane southbound from Hegenberger Road to Marina Boulevard. This will include rebuilding the Davis and Marina Boulevard overcrossings.

In addition, the High Street onramp on northbound I-880 will be closed from 11 p.m. Friday until 11 a.m. Sunday. This ramp will be repaved and a second lane will be added. Caltrans urges drivers to use the 42nd Avenue or Fruitvale Bridge onramps when coming from Alameda. This will last until the end of the month.

Q Could you please find out why there is a need for a stoplight on San Pablo Avenue at John Street in Pinole? There is a cement divider prohibiting a left turn onto John Street, and likewise cars on John Street cannot make a left turn onto San Pablo Avenue. There is no cross street on the other side of San Pablo. This light turns red for no purpose and cars just sit there idling and wasting gas.

Beverly Melcome

Hercules

A This signal was installed for two reasons -- to provide a safe way for pedestrians to cross San Pablo Avenue, and because the sight distance is extremely limited for vehicles wishing to turn right onto San Pablo.

Q Some San Jose police cruisers are sporting an unusual device on the roof. Black, cylindrical and about a foot tall. Qué pasó, Gary?

Jack Moore

Saratoga

A These are the department's license plate recognition vehicles, which capture license plate numbers and run them through the stolen vehicle system in order to identify stolen vehicles. Those cameras are set up to read plate numbers only.

Q There is new activity starting at Mission Boulevard/680 north. Wasn't the addition of the less than useless toll lane through this stretch on the southbound side a big enough waste of taxpayers' money?

Chris Lyons

A This is different. Ramps have been closed at night so crews can install temporary water pipelines in preparation for seismic upgrade work and replacement of water pipelines later this spring. It's part of the San Francisco Public Utilities Commission's $4.6 billion seismic improvement program launched in 2002.

Q Westbound Mission Boulevard between Warm Springs and the I-880 north onramp is in horrifically bad shape. Deep potholes that ruin tire rims and 10-foot-long grooves that toss your car around abound in this area. With all of the construction activity in southern Fremont, I assume the plan is to hold off on road repairs until work is completed.

However, I don't think we can wait that long (2-3 years?). This area is in terrible shape and is now creating "dodging drivers" who, realizing what they are about to hit, suddenly swerve around these road surface monsters.

Can anything be done or is it all bad news until the construction work is done?

Tim Riener

Fremont

A There will be a shift in traffic lanes next weekend and some potholes will be filled. But the entire road won't be fixed until the BART construction ends here in another couple of years.

Q Why does the entrance ramp onto southbound Highway 85 from south El Camino Real in Mountain View make a sharp right turn? There are deep markings on the road where I assume surprised drivers have hit the curb.

Fran Lee

Palo Alto

A It's almost a 90-degree turn in order to be more pedestrian-friendly. Remember, there are two high schools near here, a popular park and a busy hospital.

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