Climate Change.... Rising sea levels.... trying to go carbon-free on energy...

So, the San Francisco (,California, USA, Earth) bay has a somewhat narrow opening, through which tides flow reliably every day. There's enough energy in that huge volume of moving water to power nearly the whole region, including Silicon Valley.

Combine that with rising sea levels, which would flood much of Silicon Valley, SF Airport, Foster City, Oakland ports, etc...

So, rather than build dumb levees to protect just a few parts of the SF Bay:

Build one huge dam under the Golden Gate Bridge, and put turbines in the dam.

As long as the sea doesn't rise too much, you get tons of energy, with very short transmission losses before it's used by 8 million locals. When it rises too far, "Goodbye energy. Hello flood protection for the entire Bay."
-- sophocles, Mar 20 2009

Tidal power program for San Francisco? http://www.sfbg.com...try_id=3960&catid=4
SF Bay Guardian article from 2007, detailing various old approaches. [jutta, Mar 20 2009]

Mayor asks Feds for permit for wave energy project. http://inspiredecon...t-of-san-francisco/
"This morning, San Francisco Mayor Gavin Newsom announced a preliminary permit application sent to the federal government for a wave power project off the coast of California. The project promises to bring wave energy and jobs to the Bay Area." [jutta, Mar 20 2009]

+2 meters, bye bye shipping anyway. http://flood.firetr...8,-122.0375&z=7&m=2
Take a look at how big an area we'd save with a dam [sophocles, Mar 20 2009]

Excellent!
-- bungston, Mar 20 2009


You'd be blocking a shipping route, so dam is out - but tidal power in the Bay has been discussed for quite a while. See link.
-- jutta, Mar 20 2009


Yeah, I'm thinking bigger than that. What's been proposed so far are too small & timid. When sea level rises: screw-it, the Bay environment will be destroyed with industrial sites under water, leaking. The docks also will be underwater.

Wihout a dam, turbines only get a very small fraction.

As for the shippers, put a dock on the dam, and then rail connections, or even ferries in the bay.
-- sophocles, Mar 20 2009


When you look at the map (link), it's pretty clear that - like it or not - damming the entire SF bay at Golden Gate makes the most sense by far when sea levels rise.

Even at just 1 meter, we've lost the shipping ports & airports. At 2 meters, you lose massive farmland, and even part of the Sacramento Airport.

The size of levees you'd need to just protect the major sites (the airports, ports, major industries, and 10% of the population), would be >100x larger than the size of the dam under Golden Gate.
-- sophocles, Mar 20 2009


you can have shipping and a dam. You just need locks. Lochs? Those things you can fill up with water so the ship floats up.
-- bungston, Mar 20 2009


Gets me thinking of a giant bath tub then [bungston].
-- blissmiss, Mar 20 2009


That sounds like a good sequence.
-- bungston, Mar 20 2009


Lochs tend to make things quite a bit slower.

If you're damming the SF bay, why not just let all the water ways into it flood the owens valley? Getting fresh water is tough these days...

On second thought, getting vegetables is tough these days too, so scratch that idea.
-- ye_river_xiv, Mar 22 2009


Once dammed, we could also take the salt out of the bay over time, with the salt-flats in the south bay that are already there anyway.

Then, the remaining (lower) volume of the whole bay could be used as a drinking water reservoir.

These radical changes may not be appealing short-term, but are likely the best thing long-term.
-- sophocles, Mar 23 2009



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