I think we should dig the California viaduct deeper. Make it one long lake. Or dig giant water holes all along it. All the excess water can just fill up the holes along its 700 mile length. No idea if it's practical(probably not), but watching all that water flow into the ocean this winter seemed like such a waste.
The WRCB's plan is to store 600,000 acre feet of water which is 26,136,000,000 cubic feet. If we took 500 miles of viaduct (2,640,000 feet) at an average depth of 30 feet and average width of 40 feet ( = 3,168,000,000 cubic feet) and dug it 10x deeper, we'd be styling.
I mean, a 300 foot trench along the middle of California is doable, right?
Yup, though we don't consider it a problem, that's just the simple math. Our solution tunnels down 1 mile deep and excavates an underground reservoir. While this may sound extreme, it's entirely feasible and cost-effective. We can say that with confidence because we're basing our analysis on research from the U.S. Department of energy. We link to that research on our website if you're interested.
It seems to me that if you need to dig a well that deep you have utterly failed to address the real problem: you are using MUCH more than falls on the ground. Wait a few more years and you'll just have to dig an even deeper well. It's just postponing the inevitable. [1]
With that principle in mind, I'm not sure I care if deep resources are polluted for a few hundred thousand years.
[1] Mexico is rapidly improving economically; it may make sense for them to postpone the real solution until such time as they can afford to desalinate and ship water long distance.
Interesting idea: digging a 65 story hole and lining it with a building. It may be uniquely suited to Mexico City (on an ancient lake bed). In most places you would have to remove 600 feet of bedrock, not a cheap proposition.
I do think the borehole plan (3km deep, rather than 400m deep) is better, although it is more speculative and this proposal has the overwhelming advantage that it’s being enacted.
If you want to go deep enough for the system scale to be reasonable, you have to get a big drilling rig. You'll hit rock within a couple hundred feet or perhaps a thousand, but I'm not sure of anywhere in the world with 5,000-10,000 feet of dirt.
The problem with going shallower is that the system capacity is directly proportional to depth and weight. Too shallow and you have to have huge weight and that means a large diameter hole and really big cables and such.
But going deeper requires drilling through rock, and aquifers which are located within the rock. That means big regulatory hurdles because nobody wants to poison the aquifer on accident. Plus the large costs of drilling through rock.
I really like the idea from a theoretical standpoint. It's very elegant. But it doesn't seem practical from an economic or regulatory standpoint. If there are places where you can get the diameter and depth for free, it's clearly genius. But I don't think purpose-drilled holes for this will become a thing -- at least barring some kind of immense breakthrough that I can't even imagine.
That's not an insurmountable problem, it just costs more money to deal with. People have been building structures below the water table for hundreds of years using cofferdams and caissons. Very realistic, just a bit pricey.
To be honest I'm pretty doubtful the economics of excavating a reservoir are going to work. It needs to be very big and very deep, which is going to be very expensive unless you're planning to go all Edward Teller (don't go all Edward Teller).
The WRCB's plan is to store 600,000 acre feet of water which is 26,136,000,000 cubic feet. If we took 500 miles of viaduct (2,640,000 feet) at an average depth of 30 feet and average width of 40 feet ( = 3,168,000,000 cubic feet) and dug it 10x deeper, we'd be styling.
I mean, a 300 foot trench along the middle of California is doable, right?
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