crawl speed through the Oakland Wye tunnels....

MalcoveMagnesia's picture

I've noticed that trains going through the curves of the Oakland Wye tunnels (the tunnels everyone goes through going into and out of Oakland near the West Oakland station) go at walking speed.

Why is this?

Noise issues or potential derailment issues if the train goes faster or?

boopiejones's picture

i totally notice that and it bugs the crap out of me. interestingly, the tracks are extremely banked going into the tunnel from macarthur, so it seems to me like they were built for speed even though they are fairly sharp curves (by bart standards anyway). they are so banked, in fact, that i find myself struggling to avoid sliding into my seatmate because the trains aren't going fast enough to hold me in my seat.

seems like it would be safer to travel faster. at least fast enough to counteract the gravitational forces of the banked track.

there have been a couple of derailments in the WYE so that is a factor. there are speed limits through out the system and they are in blocks, decreasing to 36 mph as you approach stations and increasing as you leave. you might be going slow because the route ahead is aligned against your train so it creeps along until it gets a route then it goes up near the speed limit. if a train shot out of lake merritt to the city (a 100 train) at 36mph and there was a train coming off of the C line (a 300 train) to the city at the same speed one of the two would have to come to a screeching halt because they have to both use the same track to the tube. i could just hear the complaints then, and the lawsuits for broken limbs. every TO wishes their train could just shoot to the end of the line at the maximum speed but it's just not possible.

The Oakland Wye is a complex tunnel system starting with a vertical three subway tunnel layout at 19th St. Stn/12th Stn., coming out as a three lateral subway at the Jefferson St. portal and a two subway tunnel at Lake Merritt. Factor in a combination of 715 foot long trains (10 cars) equal to the height of the TransAmerica building, to shorter combos of 5-4-3 car trains running from Fremont to Richmond, Pittsburg to Daly City, Dublin to SFO and Fremont to Daly City (plus the reverse direction). All within a 24 square block area under downtown Oakland. I don't know the number of track switches, power feeds and whatever else, but each one must be properly aligned to avoid a derail. Although trains don't intersect, trains do feed into one or more tracks headed in the same direction. Super complex.

Here's a piece of triva: From Lake Merritt to West Oakland, there is a very sharp curve that actually jolts passengers. During the construction of the Wye, a hardware store (Smity's?) refused to sell the land to BART so the engineers realigned the tunnel to miss the property line - not sure about eminent domain issues at the time.

I heard about that, the guy is long dead now, but BART still has to deal with that bend

AntMoOAK's picture

That's interesting... I'm curious about how that played out.. I'll be in the Oakland History Room this weekend reading up on Smitty. This isn't the C. Markus (Ace) down on 3rd Street No ? They made provisions for one store but an entire thriving neighborhood was decimated (in part due to BART for the elevated trackway).

It's been that way since the derailment last year. Same operator on that train found a deceased passenger on another train at the end of the line a few months ago. Some people have all the luck.

AntMoOAK's picture

"It's been that way since the derailment last year."

Hasn't it been slow around the Wye since that BIG derailment in the tunnels after 12th street about 15 years ago... back when they used to run trains "backwards" (may be using the wrong term) at high(er) speeds in that area ?

Yup.. Back when one half the car went one way and the other half went the other.. (oops) It was like the last train of the night, running the opposite direction on that track than normal and the rails were worn out..

They used to run the trains alot faster when they hit the transbay tube also.. Past 10 years or so, they slow down conciderably as they enter the tunnel.. After your ears get pressurized the train speeds up.

another factor for train speed: of the rolling stock, the older C cars' electric motors are DC. There is a huge difference between running the train at 80mph vs. 70mph, as far as wear and tear to the electric components; basically, 80mph is too much for the DC motors to take, so all trains are limited to 70mph now. Central isn't supposed to cheat by speeding a train up to 80 (if it gets behind schedule).

I heard all cars have been converted to AC with an on-board inverter turning the 1kv off the third rail to AC. I agree, the DC motors were, ah, er primitive.

AntMoOAK's picture

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most cars have been upgraded, except the 300's, 400's and 2500's, which are the C (or C2) cars. These still have DC motors, run via a "chopper" circuit to control speed. unsure when these cars will be upgraded.