Q Our daughter and her family have recently moved from Oakland to Walnut Creek. She teaches in Fremont and fortunately doesn't have to be at her school until 10 a.m., so her commute to Fremont is only taking her an hour.

Lucy DiBianca

Walnut Creek

A I'd say an hour is pretty nasty, but ...

Q The problem is her return trip is taking a long stressful hour and a half in stop-and-go traffic. She tries to leave as close to 3:30 to 4 p.m. as she can. As you can imagine, that means she has to hurry to prep for the next day, confer with students and try to attend staff meetings, all before making a quick getaway to beat the traffic on Niles Canyon Road to Interstate 680 near Pleasanton. She has not been able to find a partner to use the carpool lane.

Do you have any suggestions to help her find an easier return route while at the same time allowing her a bit of leeway time-wise so she can either stay a little longer or at least not panic that she'll get home to Walnut Creek in time to meet her children's day care scheduling?

Lucy DiBianca

Walnut Creek

A Oh, Lucy, I feel sorry for your daughter, for I know that panicky feeling, but I know of no shortcuts along 680. Other than adding auxiliary lanes through Danville, there is no imminent carpool lane widening planned in Alameda or Contra Costa counties, and the installation of metering lights along 680 is years away.

She appears to be doing the best she can by avoiding peak driving times. Maybe some 680 veterans have some tips.

Q What are the rules for the new flashing crosswalk signs near schools? There are several in Pleasanton. They continue to flash for several seconds after pedestrians are well past the crosswalk. Other drivers honk if you wait until they stop flashing, but I heard of someone who was ticketed for proceeding even though the crosswalk was clear.

Roma Bishop

Pleasanton

A If the pedestrian has cleared and the lights are still flashing, it is OK for drivers to proceed, though it's important to check that no other pedestrians, especially children, are about to cross. The flashing crosswalk lights are a warning device, not a traffic control device like a signal or stop sign. Pedestrians need to cross when it's safe to do so, and once they are in the crossing cars have to yield to them.

Q I recently made my first trip over the new Bay Bridge span for a medical appointment in San Francisco, and a question arose as I headed back east. The new span appears to be at least 15 to 20 feet closer to the water than the old cantilever span it replaced. Won't this present a problem for commercial shipping? As I recall some of the large ships were already having clearance problems with the old span.

Delta Bob

Rio Vista

A The primary shipping channel is under the west span. The passage beneath the self-anchored suspension portion of the new east span is a secondary channel, and is the only deep water east of Yerba Buena Island.

The new east span gets to precisely the same elevation as the old span near the tunnel. Gone is the steep rise westward or steep decline eastward previously known as "the Incline Section" just off the Oakland shoreline. In its place is a much more gradual slope.

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