Q Would you vote the 101-880 interchange as the biggest mess on Bay Area highways? The 880 south to 101 south and the 101 north to 880 south are the biggest messes.

Ryan Langdon

A This interchange is a top contender for the biggest mess award, but I'd rate the Interstate 80 drive to the Bay Bridge as the worst. And here is some not-so-good news:

A study by the Metropolitan Transportation Commission on ways to ease the 101-880 mess was to have begun two years ago but has not yet been launched. And it needs to be. John-the-MTC-Man says it's his guess that the daily traffic flow through this interchange is comparable to that of the Bay Bridge. "When you look at this interchange from this perspective, you might come to the conclusion that at least a study of the interchange is overdue," he says.

Traffic on State Highway 24 near the Caldecott Tunnel, Berkeley, Calif.
Traffic on State Highway 24 near the Caldecott Tunnel, Berkeley, Calif. (D. ROSS CAMERON)

We can perhaps all agree on that.

Q So, many years have passed and I am still curious about what the fourth bore of the Caldecott Tunnel will be like. Will the lighting at the entrance be bright enough so that drivers aren't likely to slow to enable their eyes to adjust to a different light level? Will the tunnel be slightly wider? They have been playing with differing light levels in the existing tunnels for years. I am anxious to drive through the new tunnel. We have been paying for it for so long.

Jerry Kosel

Clayton

A That you have. The portions of the tunnels near the eastern and western portals have been designed to allow natural light to filter inside to help motorists gradually adjust to the lighting as they enter and exit the tunnel.

The new fourth bore will also have concentrated electric lighting at the entrance and exit to serve the same purpose. The settings of the lighting will be similar to bore No. 3's lighting -- six levels of daytime contrast lighting, as well as a high level of interior lighting that can be dimmed or raised as needed.

Perhaps the most noticeable difference between the existing bores and the new tunnel will be a 10-foot shoulder on the northern wall of the fourth bore, and a two-foot walkway along the southern wall. In the event of a serious emergency in the tunnel, motorists would be able to leave their cars and walk to the seven cross-passages that are now being completed between bores 3 and 4.

Caltrans says it's on schedule to open the fourth bore late this year.

Q In regards to the question by Fredo O'Yang on the afternoon commute being worse than the morning at the Caldecott Tunnel:

I also believe there are more people on the road in the afternoon. I do the reverse commute each day from Oakland to Lafayette and I frequently encounter backups that are worse in the afternoon. However, I am looking forward to the opening of the fourth bore of the Caldecott Tunnel. It will really help my commute.

D. Claunch

Oakland

A Others also have weighed in on Mr. Yang's observations.

Q Reader Wang asked about increased traffic during the afternoon commute along Highway 24. My theory is that many Solano County commuters who used to use Interstate 80 through Berkeley and Richmond switched to 24/680 when the new bridge at Benicia opened. We seem to be backed up again on Highway 24 through Lafayette.

Donald Hall

Orinda

A And ...

Q Other reasons Caldecott commute is worse in evening: Commute direction is uphill going through tunnel. And it uses only the old tunnels, which are narrower and, I think, darker. Hence drivers go slower.

Dan B.

A Good point. Bores 1 and 2, which opened in 1937, are a mere 22 feet wide. Bore No. 3 opened in 1964 and is 28 feet wide. The new tunnel is 36 feet wide, including two 12-foot lanes.

Q I drive very seldom, but I'd like to add to your answer to Fredo. I work in Oakland and get on 24 east at about 20th Street. When I get on there are six lanes, all eastbound. Then it drops down to five lanes, then four, and just about then, both Highway 13 northbound and the Claremont Avenue/Tunnel Road traffic southbound merges to go east on 24. That's six lanes merging down to two.

No wonder it takes longer.

Sonny Vanwest

Lafayette

A On this we can certainly all agree: The afternoon commute is the pits.

Q The Kennedy Tunnel (precursor to Caldecott) was finished in 1903 and cut FOUR HOURS off the travel time from Oakland to Lafayette, according to the plaque on Tunnel Road at the base of the old tunnel. We're thinking you could almost walk from Oakland to Lafayette in four hours.

Sue Stanton

Castro Valley

A I'm thinking you may be right.

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