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California Is Drilling for Water That Fell to Earth 20,000 Years Ago

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21–30 of 73 posts

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#21
post #4

One solution to producing water is desalination. You can effectively get unlimited amount of water, but you pay for it in energy. A quick Google search finds that there's a desalination plant under construction in Carlsbad, California.

There's also the problem of what to do with the high salinity waste water that is generated from the process. Simply dumping it back into the ocean can cause environmental problems.

What about putting the waste water in a salt pan?

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#22
post #9

All of this reminds me of a trip I took about 10 years ago to Palm Desert. Even then I was stunned by opulence of their water use and the utter disregard for sustainability. It's a city built in the desert that regularly reaches 100+ degrees, and yet every house had a bright green grass with sprinklers running constantly. One of the main attractions was their huge amounts of golf courses, that were of course always k…

That's infuriating. Agriculture is the main consumer of water in CA by a mile, but the sort of self-indulgence you describe sets a disproportionately bad example and avoidably confuses the issue.

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#23
post #7
post #6

Earlier quoted context omitted.

MIT Technology Review wrote a great article on this: http://www.technologyreview.com/featuredstory/533446/desalin...

That is a good summary. A friend of mine is looking at putting a passive desalinator on the ocean floor off the coast of Monterey. Basically its a pipe with the permeable membrane surrounding the submerged collector. The pipe carries fresh water to the surface and as you pump out fresh water, the pressure of the ocean at depths of up to 1000 meters pushes in more water through the membranes, desalinating it in the pr…

Sounds like the MaHaLo Hawaii Deep Sea Water project[1]. They use that water in Ocean Vodka interestingly enough[2], which is where I found out about it. On the tour they indicated this project seems to be working out quite well.

[1] http://hawaiideepseawater.com/source [2] http://oceanvodka.com/our-vodka/ingredients/

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#24
Water waste is everywhere. In deserts we water golf courses. In cities we hose down sidewalks to reduce dust and dirt. A huge percentage of the food we produce that uses water to generate gets disposed of. Then there's this:

"Initial estimates are that when fully operational, the Utah NSA Data Center will use as much as 1.7 million gallons of water per day."

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#25
post #7
post #6

Earlier quoted context omitted.

MIT Technology Review wrote a great article on this: http://www.technologyreview.com/featuredstory/533446/desalin...

That is a good summary. A friend of mine is looking at putting a passive desalinator on the ocean floor off the coast of Monterey. Basically its a pipe with the permeable membrane surrounding the submerged collector. The pipe carries fresh water to the surface and as you pump out fresh water, the pressure of the ocean at depths of up to 1000 meters pushes in more water through the membranes, desalinating it in the pr…

What does all that extra salt do to the chemistry of the water in that area?

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#26
post #12

Earlier quoted context omitted.

You can do it, but it turns out the work to pump water up to 1400 psi in a pressure vessel before it goes through a reverse osmosis membrane is about the same as the work to pump desalinated water up from the bottom of the ocean at 1000 meters. There are different inefficiencies in each situation, but I'd assume maintaining equipment 1km below the sea would trump them all.

I think he really means you bail the water from the top rather then pump it, leaving an airgap at the top that the pressure from below gradually fills with more water through the membrane. But then again unless you bail all the water, that leaves only a small pressure differential, and if you bail it all, it gets less efficient as it fills back up and the pressure differential gradually reduces and lifting it from th…

As described in the paper the top 20 meters of the pipe to the surface are emptied (the paper refers to a 30 meter 'pump head' which I believe is the distance below the surface that the water has been pumped out of the pipe). The part on the surface of the ocean is what looks like a giant bucket of sand on the outside (it is supposed to be below the level at which coral grows). The pipe fills with fresh water at some rate (unspecified by the paper) and you can pump it out at the top when you need it. The part on the bottom of the ocean requires no maintenance.

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#27
post #24

Water waste is everywhere. In deserts we water golf courses. In cities we hose down sidewalks to reduce dust and dirt. A huge percentage of the food we produce that uses water to generate gets disposed of. Then there's this: "Initial estimates are that when fully operational, the Utah NSA Data Center will use as much as 1.7 million gallons of water per day."

where does that water go? evaporated?

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#28
post #7

Earlier quoted context omitted.

That is a good summary. A friend of mine is looking at putting a passive desalinator on the ocean floor off the coast of Monterey. Basically its a pipe with the permeable membrane surrounding the submerged collector. The pipe carries fresh water to the surface and as you pump out fresh water, the pressure of the ocean at depths of up to 1000 meters pushes in more water through the membranes, desalinating it in the pr…

Sounds like the MaHaLo Hawaii Deep Sea Water project[1]. They use that water in Ocean Vodka interestingly enough[2], which is where I found out about it. On the tour they indicated this project seems to be working out quite well. [1] http://hawaiideepseawater.com/source [2] http://oceanvodka.com/our-vodka/ingredients/

Interesting that their "3000 feet" corresponds to the 1000 meters I read in the paper. I could not find anything on their site though that actually talked about the extraction process.

Re: California Is Drilling for Water That Fell to Earth 20,000 Years Ago

#29
post #9

All of this reminds me of a trip I took about 10 years ago to Palm Desert. Even then I was stunned by opulence of their water use and the utter disregard for sustainability. It's a city built in the desert that regularly reaches 100+ degrees, and yet every house had a bright green grass with sprinklers running constantly. One of the main attractions was their huge amounts of golf courses, that were of course always k…

Palm Desert and portions of Southern California get their water from a local aquifer and the Colorado River, unlike the Central Valley and most of the state, and therefore are not directly affected by the drought in the same way as the rest of the state.

Visible urban water usage like lawn watering is a small fraction of the water usage in California, and even if every lawn stopped getting watered it wouldn't come close to solving the issue.

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