Why not tunnel the tracks and central under Castro?

Let's see, the tracks need at least 22ft clearance. Add a few more feet for the thickness of the bridge structure supporting Castro Street. At a 1% grade, it takes half a mile for the tracks to drop/rise 26-27ft.

So you can't just tunnel the tracks under Castro Street. You have to tunnel/trench the tracks for at least a mile.

In contrast, if you tunnel the street under the tracks, the street needs only 16ft clearance, and the maximum grade can be several times higher, significantly reducing the length of the tunnel/trench required.

Adding to Darin's comment, submerging the tracks at Mountain View station has the additional challenge of dealing with Stevens Creek just south of the station.

The presence of nearby creeks is also a challenge for making subterranean stops at Palo Alto and San Antonio stations.

The 1% grade mentioned by Darin is the maximum allowable by Caltrain. Also, the 22 ft. clearance applies to the current unelectrified trains. The electric trains of the future would need even more clearance if they stick with the double-decker cars with the overhead catenary.

Closed at the tracks with a new bike/ped under-crossing? Yes please!!!

When Denver had to have this solution, putting in grades to allow VEHICLES to go underneath the busy BNSF trains with mile-long consists worked! To close off Castro/Moffett will create a " pocket " that has a risk of losing businesses. The gotcha: No pedestrian or cyclist would be able to go up or down such a grade. Is Dog City II about to happen?

Close Castro and get the Rengstorff grade separation going.

Glad the decision has been supported. Time now to move forward and close her up. The old through-way served us well but times have changed...actually they changed about 20 yrs ago, but we're just now making the needed adjustments to things. Anyway, I cant wait to ride through the new tunnel :)

Look to lively California Ave in PA as an example of what can be. I expect the businesses near the more quiet "dead end" of Castro will become the prime spots. Foot traffic buys things, car traffic clogs things and keeps buyer away.

Why are you people all posting here?

This was a duplicate copy of a Voice story nearly two months old. It appeared in late June, and got numerous comments: Web Link">Web Link

Then, early yesterday (12:46 AM), someone signing above as "Gabe" decided for some reason to dredge up the website's secondary "Print" copy of the story, and add a comment about tunneling the tracks under Castro (an unrealistic option whose obstacles have already been explained, time and again, even long before this particular Voice story appeared in June).

The Voice website has a quirk of archiving secondary copies of stories that appeared online before they were in print. Many people know to ignore the secondary story copy (even when it isn't two months out of date). If you really want to hash out, yet again, all the arguments about closing Castro, then comment on the original story, where many more details and answers appeared already in comments: Web Link">Web Link

why does it bother you so much?

I think this is really great!