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Message from Mexico: U.S. Is Polluting Water It May Someday Need to Drink

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21–30 of 217 posts

Re: Message from Mexico: U.S. Is Polluting Water It May Someday Need to Drink

#21
post #13

Earlier quoted context omitted.

Would conservations (like people giving up luscious grass lawns) be enough to sustain the population in the west? (In your opinion.)

Well, about 80% of water use (in the west) is for irrigation purposes. Ideally, making farmers pay market (and externality adjusted) rates for their water would discourage them from growing plants which need a lot of water per unit food (like alfalfa). We could get a LOT further with water-aware legislation for what farmers can grow (or if you prefer a libertarian viewpoint, have the government stop subsidizing water…

How much of that 80% of water used for irrigation is lost to evaporation and such. As the water is essentially 'free' to the farmers, they have little incentive to use it efficiently, so it would probably be cheaper to use sprinklers than more water efficient methods like drip irrigation.

Also, is the problem really that the government subsidizes water. As I understand it, there is a naturally occurring aquifer that is currently being used at free market rates. We would need the government to tax this to reduce usage.

Re: Message from Mexico: U.S. Is Polluting Water It May Someday Need to Drink

#22
post #13

Earlier quoted context omitted.

Would conservations (like people giving up luscious grass lawns) be enough to sustain the population in the west? (In your opinion.)

Well, about 80% of water use (in the west) is for irrigation purposes. Ideally, making farmers pay market (and externality adjusted) rates for their water would discourage them from growing plants which need a lot of water per unit food (like alfalfa). We could get a LOT further with water-aware legislation for what farmers can grow (or if you prefer a libertarian viewpoint, have the government stop subsidizing water…

a source: https://en.wikipedia.org/wiki/Water_in_California

A bunch of water also goes back to the environment, but I don't think we want to take that.

Re: Message from Mexico: U.S. Is Polluting Water It May Someday Need to Drink

#23
post #6

Funny for this to come up now. I'm reading Cadillac Desert by Marc Reisner now which is all about water policy in the western US. The short answer is that we consume WAY more water than all of the precipitation on the entire region can support so we end up depleting the aquifers. Eventually (likely within my lifetime) those will dry up and they we will have to either start diverting water from Canada and Alaska, or d…

Pump seawater to Nevada and cover it in desalination greenhouses. http://www.seawatergreenhouse.com/

How is this better than local rainwater collection? Rainwater is desalination, you just cheated and let nature do the expensive part. Heck, lots of rainwater is already collected in gutters/roof drains, but is contaminated when it falls on the ground instead of into a tank.

For irrigation all that is necessary is to soak the rainwater in as soon as possible to prevent evaporation and runoff, since potability is not a requirement. This is even cheaper than rooftop catchment.

Of course you may need to re-green the upwind deserts first (since ~80% of terrestrial rainfall comes from plants, not evaporation), but we already have that technology. http://www.youtube.com/watch?v=K1rKDXuZ8C0

This is hardly unprecedented. The CCC installed thousands of miles of swales during the Depression (that function to this day), but nowadays most people don't even know what a swale is.

Re: Message from Mexico: U.S. Is Polluting Water It May Someday Need to Drink

#26

Why is it so difficult for people to understand that regional borders are more often than not a human concept? You do not live in the United Bubble of America! That having been said, wasn't there an article yesterday about how 30% of Californian pollution comes from China? Or a few weeks ago that radiation from Japan is hitting our shores? This is not what they meant with "Think locally, act globally."

There was no actual message sent by Mexico, just a red flag raised by a journalist: "don't poison your own water, even if you don't plan to use it right now". Mexico City didn't plan to use water that deep, but they have to.

Re: Message from Mexico: U.S. Is Polluting Water It May Someday Need to Drink

#27
post #24

Has anyone tried desalination with geothermal sources?

Two challenges off the top:

⚫ Geothermal is available in limited areas. Few of those are proximate to salt water (though in Japan, Hawaii, and the Philippines this might be the case). I'm not aware that freshwater supplies are critically limited in any of those areas, however.

⚫ Geothermal itself tends to have substantial water requirements as a heat transfer / working fluid. Replenishing groundwater liberated through generating activities is a concern in many fields.

Re: Message from Mexico: U.S. Is Polluting Water It May Someday Need to Drink

#28

For example, in eastern Wyoming, an analysis showed that it would cost half a million dollars to construct a water well into deep, but high-quality aquifer reserves. That, plus an untested assumption that all the deep layers below it could only contain poor-quality water, led regulators to allow a uranium mine to inject more than 200,000 gallons of toxic and radioactive waste every day into the underground reservoirs…

It is called "not while I am alive" policy. When someone in office does something which won't impact anything when they are alive they can score points with special interests by helping get their project approved. Mostly though this is just another attack on Fracking.

Re: Message from Mexico: U.S. Is Polluting Water It May Someday Need to Drink

#29

For example, in eastern Wyoming, an analysis showed that it would cost half a million dollars to construct a water well into deep, but high-quality aquifer reserves. That, plus an untested assumption that all the deep layers below it could only contain poor-quality water, led regulators to allow a uranium mine to inject more than 200,000 gallons of toxic and radioactive waste every day into the underground reservoirs…

The current nuclear industry has some serious downsides. The only reason established nuclear is presented as ecological is due to the discussion about climate impact. Without the CO2 blinkers on though, it is pretty fucking messy.
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