Virtual Tour of the Posey Tube - Non-Public Areas

[@VegHui]

I enjoyed this virtual underwater tour getting deep into the trenches

[@nathanwalker826]

Fantastic. I grew up in Alameda, and wondered just what was inside those buildings. My parents always just said "Fans". While they were right, this really brings it all together.

[@VegHui]

The litter 😔 bottles at 18:21

[@brianmcmahon7711]

This is fabulous. I have been through the tube 10,000 times via car, bus, bike, and foot. I've always wondered what was inside the building. I would love to go on a tour if they are still available.

[@calpreservation]

@brianmcmahon7711 Thank you! Oakland Heritage Alliance occasionally offers in-person opportunities.

[@ostrich67]

I once rode a shopping cart from Alameda to the bottom and walked the rest of the way to Oakland. Don't ask why.

[@janisclark8125]

Thanks for this video. Question: why aren't all tubes/tunnels WELL lit?

[@calpreservation]

We are curious too. Just a guess: Maybe the lighting system is based on earlier technologies that (while historically accurate and in keeping with the nature of the tube itself) cannot be easily upgraded for modern lighting or energy characteristics without fundamentally changing the nature of the space and its original design? Some sort of like the ambient light of these tubes in their characteristic orange glow; while others prefer the bright white light of modern LEDs?

[@andreadaniel4362]

Are there any plans to add scrubbers or filters to the area where exhaust goes back outside?

[@calpreservation]

Great question. We'll see what we can find out

[@StevenBColman]

It's worth noting that the Posey Tube provided the proof-of-concept for building a tube in the bay mud that would be similar to how BART's transbay tube would be built some 40 years later.

[@stephanielucas8203]

Random question, but something I wonder any time I'm in the Tubes: what's the weight of the water overhead at the deepest point? Anyone know?

[@calpreservation]

Totally random question, but we wonder the same thing! Wish we could give you an answer 🙂

[@Yleas-qs5xh]

Water is about 63 pounds per cubic foot, so just multiply by how deep the tube is submerged. I didn't see any info on depth, but including approaches its about 4000ft long with a max grade of 4.5% so no deeper than 90 feet. So probably more than 4,000 pounds per sq. foot and less than 3 tons per sq ft.