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The Colorado River is shrinking

sciencemag.org

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Re: The Colorado River is shrinking

#221

Post by bsder »

dogman144 wrote: post #49

Does anyone have educated views on desalinization tech? That seems to be the few ways out of this that's totally within our control. I imagine we'll rob Peter to pay Paul with it via extincting a bunch fish we didn't mean to in desal turbines or something unexpected like that, but that aside..

> That seems to be the few ways out of this that's totally within our control.

Desalinization works just fine--if you have an ocean nearby.

In California, desalinization plants keep getting built and will eventually be able to handle the water needs of people near the coasts.

However, there is no way desalinization can ever support farming. And that's 80+% of the water consumption.

Either you shut down the farms now or when the water runs out--that's the only option.

Re: The Colorado River is shrinking

#222

Post by dogman144 »

bsder wrote: post #221
dogman144 wrote: post #49

Does anyone have educated views on desalinization tech? That seems to be the few ways out of this that's totally within our control. I imagine we'll rob Peter to pay Paul with it via extincting a bunch fish we didn't mean to in desal turbines or something unexpected like that, but that aside..

> That seems to be the few ways out of this that's totally within our control. Desalinization works just fine--if you have an ocean nearby. In California, desalinization plants keep getting built and will eventually be able to handle the water needs of people near the coasts. However, there is no way desalinization can ever support farming. And that's 80+% of the water consumption. Either you shut down the farms now…

Why can’t you pipeline desalted water? Or is there not enough throughout. Take oil tech for refinery storage and transport and use it for water.

Re: The Colorado River is shrinking

#223

Post by User23 »

ajross wrote: post #36
User23 wrote: post #24

Earlier quoted context omitted.

Are there good figures on how much of that water is “wasted” and how much ends up replenishing groundwater reservoirs? Utah isn’t that close to the Pacific so that water has a lot of opportunities to do something other than flow into the ocean.

Virtually all agricultural irrigation evaporates. It doesn't even run off into local streams (which you can verify by, heh, the lack of local streams in the Utah desert), much less seep into the ground. Underground aquifers fill over decades and centuries, and in this environment, almost always laterally, not from seepage from rainfall. I think the demand for proof needs to go the other way, honestly. Presumptively t…

> Virtually all agricultural irrigation evaporates. It doesn't even run off into local streams (which you can verify by, heh, the lack of local streams in the Utah desert), much less seep into the ground.

The evaporation figures I can find range from 30% to 50%, which is hardly virtually all. I've never been to the Utah desert, but in the California desert I've dumped out water and watched it disappear into the ground. The absence of streams only indicates that seepage and evaporation together get all of the water that would otherwise flow in them.

> Underground aquifers fill over decades and centuries, and in this environment, almost always laterally, not from seepage from rainfall. I think the demand for proof needs to go the other way, honestly. Presumptively this water is pretty clearly "wasted".

Unconfined aquifers will fill as fast as rainfall can seep in, which depending on the area can be a lot less than decades.

How is letting the Colorado flow into the Pacific more of a "waste" than using that water to grow food and letting the excess seep into the water table and fall as rain on the other side of the Rockies?

Re: The Colorado River is shrinking

#224

Post by tsimionescu »

t0mbstone wrote: post #216
simiones wrote: post #161

Earlier quoted context omitted.

All of those things are likely to increase our global warming issues, as they are highly energy consuming in several ways. If we want any semblance of current society to keep chugging along 50-100 years from now, we need to reduce our production of almost everything, energy most of all. There is simply no other solution to stop catastrophic global warming.

Energy consumption is not a problem, provided it comes from the sun. The sun is going to burn and blast the earth with energy, whether we harness it or not. Harnessing the sun's energy and applying it towards water desalination and distribution would allow us to grow all sort of plants (including trees) in areas that would otherwise be unable to sustain plant growth. Plants are composed largely of carbon that is extr…

> Energy consumption is not a problem, provided it comes from the sun. The sun is going to burn and blast the earth with energy, whether we harness it or not.

Harnessing solar energy is not free - you still need to build solar panels or other kinds of solar plants. Producing these requires metals that need to be mined, forged and transported. Solar energy only works for half the day, and is only plentiful part of the year.

Not to mention, today we need to decommission all fossil fuels in the world and replace them with renewables, also covering the energy needs of emerging countries. So while in some distant future of 100% renewables we could contemplate desalination, we can't spare any energy today towards new industries.

Even so, it is unlikely that we could replace all of our current energy consumption with renewables, given the huge problems with variability, in the foreseeable future.

Re: The Colorado River is shrinking

#225

Post by beerandt »

tzs wrote: post #201
anonAndOn wrote: post #47

Earlier quoted context omitted.

The US exports massive amounts of water in the form of hay and alfalfa.[0] This practice may not survive once the reservoirs completely dry out. [0] https://alfalfa.ucdavis.edu/+symposium/proceedings/2019/Arti...

Very little of the water used to grow hay and alfalfa actually ends up in the hay and alfalfa to be exported. Most of the water ends up in the atmosphere via evapotranspiration. The amount exported is something like 0.005% of the evapotranspiration amount. Here are some numbers [1] for Idaho crops. There might be some differences in Utah but they should be in the same ballpark. > Not much water is exported with alfal…

The opportunity cost is there, whether the actual water is exported or not. Especially if the local resource is somehow subsidized either directly or indirectly.

Re: The Colorado River is shrinking

#226

Post by rtkwe »

WkndTriathlete wrote: post #202
rtkwe wrote: post #159

Earlier quoted context omitted.

You can live out there with little water impact if you don't insist on importing the kind of green water intensive landscaping that the rest of the country wants. People living there is relatively ok from a water point of view (though from a power usage perspective we really should be building very different homes in that area too) it's doing farming in some of the drier parts of the US that seems wasteful when we kn…

Nitpick: in the wet areas of the country it's not that we want green landscaping, it's that it is almost impossible to not have green landscaping because of how much rain we get. Lay down a layer of rock landscaping over landscaping fabric around a home in suburban Minnesota without maintaining it (e.g. by aggressively applying weed preventer and weeding it) and in 3-5 years it will be covered with native prairie gra…

What I mean is the grass monoculture, trees, shrubs and flowers that for the ur-lawn in the US most of the us that requires a lot of extra watering to maintain.

Re: The Colorado River is shrinking

#227

Post by dleslie »

cmrdporcupine wrote: post #85
dleslie wrote: post #63

Earlier quoted context omitted.

The southern interior hosts a desert; definitely not a lot of rain there. ;) We're building rain storage right now, in the form of Site C.

Wouldn't you say Site C more of a glacial-melt supplied reservoir? EDIT: It's a dam built on the Peace, which is out of the Rockies, on the other side from most of BC. And a long way from anywhere in B.C. that will be requiring drinking water or irrigation really. The farm land that would be irrigated I would imagine would be primarily on the Alberta side.

It's a snow-pack reservoir, I think.

The intended use of the water is for power generation, but I think dams are clear model of how to build rain water reservoirs going forward.

Re: The Colorado River is shrinking

#228

Post by mynameisash »

nohuck13 wrote: post #46
ngngngng wrote: post #10

Approximately 27% of the water used in Utah comes from the Colorado River and 60% of Utahans benefit from the river. 82% of Utah water goes to farmers. Significant amounts of that water usage is to grow Cotton and Alfalfa. Two water intensive crops that are largely exported out of the country. In my opinion we have absolutely no business growing these crops in a desert, especially just to ship them out of the country…

> 82% of Utah water goes to farmers. Of the remaining 18%, ~ 8% goes to commercial/industrial use ~ 10% goes to municipal residential use (outdoor: 6%, indoor: 4%) [1] [1] https://le.utah.gov/interim/2012/pdf/00002706.pdf

I'm going to be super pedantic here because your phrasing confused me and I wanted to be clear:

It's not that 8% of the remaining 18% is commercial/industrial; it's that 8% of the total (not part of the 82% agricultural) is commercial.

In other words:

* 44% of non-agricultural use (8% of the total, within the 18% non-ag) is commercial/industrial,

* 33% of non-agricultural use (6% of the total, within the 18% non-ag) is outdoor residential, and

* 22% of non-agricultural use (4% of the total, within the 18% non-ag) is indoor residential

^Data are on page 4/16 of the linked PDF

Re: The Colorado River is shrinking

#229

Post by CountDrewku »

rtkwe wrote: post #159
CountDrewku wrote: post #100

Earlier quoted context omitted.

>In my opinion we have absolutely no business growing these crops in a desert, You might as well just say people shouldn't be living in most of the western US then since a majority of it receives very little rainfall. It's very easy to call these people out when you're not directly affected. Yes just strip them of their major sources of income. No issue there.... You need a better plan than just telling the Governor…

You can live out there with little water impact if you don't insist on importing the kind of green water intensive landscaping that the rest of the country wants. People living there is relatively ok from a water point of view (though from a power usage perspective we really should be building very different homes in that area too) it's doing farming in some of the drier parts of the US that seems wasteful when we kn…

> You can live out there with little water impact. it's doing farming in some of the drier parts of the US that seems wasteful when we know water is an issue there.

Ok then they'll use it up and the problem will solve itself.

I don't agree that you can live there and have the infrastructure to support jobs, food etc. with "very little impact"

Re: The Colorado River is shrinking

#230

Post by CountDrewku »

rtkwe wrote: post #226
WkndTriathlete wrote: post #202

Earlier quoted context omitted.

Nitpick: in the wet areas of the country it's not that we want green landscaping, it's that it is almost impossible to not have green landscaping because of how much rain we get. Lay down a layer of rock landscaping over landscaping fabric around a home in suburban Minnesota without maintaining it (e.g. by aggressively applying weed preventer and weeding it) and in 3-5 years it will be covered with native prairie gra…

What I mean is the grass monoculture, trees, shrubs and flowers that for the ur-lawn in the US most of the us that requires a lot of extra watering to maintain.

>grass monoculture, trees, shrubs and flowers that for the ur-lawn in the US most of the us that requires a lot of extra watering to maintain

It does not. I lived in the midwest for the majority of my life and never once had to water my lawn to keep everything green and alive.

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