On Dumbarton Bridge, drivers should go 55 mph

Q Why is the speed limit on the Dumbarton Bridge 55 mph and not 65 like on the San Mateo Bridge?

— Ed King, Los Altos

A There are three reasons: There are only two lanes each way on the Dumbarton, and no shoulders of any significance. The speed limit on the San Mateo Bridge was raised to 65 only after that span was widened in 2003 on the low-rise trestle portion from four to six lanes to match the configuration of the high-rise section. But here’s perhaps the most important reason. Dumbarton traffic dumps onto city streets in Fremont and on the Peninsula where speed limits can fall into the 40-mph to 35-mph range quickly. State policies won’t allow a drop from 65 to 35, but it will approve a 55 to 40 decline.

Q How is the toll vs. free direction determined on Bay Area bridges?

— Jeff M.

A All of the bridges originally collected tolls in both directions. All of the state- owned toll bridges were under the jurisdiction of the State Di- vision of Bay Toll Crossings at the time toll collection was switched to one direction in the late 1960s to minimize diversion of trips to alternate routes, reducing costs and crashes eastbound on the Bay Bridge.

Q On a drive through the Sierra foothills, the small towns have a series of speed limit signs slowing you down from 55 to 45, then 35. Then at the end of most towns is a sign “End 35 Speed Limit”. What does that mean? Go back to 45? Or 55? Or can I just drive as fast as I want like in the old days of Montana before they established a daytime speed limit?

— Arlen Stone, Morgan Hill

A A two-lane, undivided highway has a standard speed of 55 mph, unless otherwise noted. When the signs says “Resume Normal Speed” — that would mean return to the state standard of 55 mph after passing that sign.

Q My driver’s license expires in a few weeks and I have to take a written test to renew it. I tried to make an appointment via the web- site or phone, and found that no appointments were available until after my birthday. I got the earliest appointment I could find but it is about 10 days after my birthday. What will happen if I go in for my appointment and they see that my license is already expired? Is there any grace period given the delay in getting an appointment? Any suggestions?

— John Lawrence

A The DMV does not require an appointment to renew or apply for a driver license. Renewal notices go out 60 days before the license expires, so try nearby offices for a online appointment or just walk in. But don’t drive with an expired license.

Q My driver’s license will expire in October. I will be 83 years old, but I have not had a ticket in 12 years (seat belt violation) and only one other over 30 years ago. What are my chances of getting a renewal?

— Eloy Esparza

A Good, if you pass an eye test and there is nothing that warrants a closer look and requires you to take a written test. Folks over 70 must renew their license in person at a field office.