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Big water cutbacks ordered amid Colorado River shortage

latimes.com

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Re: Big water cutbacks ordered amid Colorado River shortage

#31

Post by Syonyk »

pilom wrote: post #15
no_wizard wrote: post #3

Could we feasibly just run desalination stations from the coasts and pipe the water - like oil - to fill up these reservoirs? Setting cost aside for a second, is there any reason not to do something like this?

Anything is possible for enough money but I don't think you understand how much money what you're proposing would cost. In electricity alone desalination costs around 3kwh/m^3. 3.7mwh/acre foot of water. Last year we got 9.2 million acre feet of water in the Colorado River of the allocated 15 million acre feet. So if we say we want to supplement flows with just 2 million acre feet of desalination water, that's 7 Pwh…

Hm. Your numbers and mine don't match by a few orders of magnitude. I came up with 2.5GW sustained, which is (2.5GW * 24h * 365) 21900 GWh ~= 21TWh/yr. Big, but not the same as your value.

An acre foot is 1233 m^3, and at 3kWh/m^3, that's 3.7 MWh/acre foot. Math checks out so far.

Times 2000000, that's 7400000 MWh / 7400 GWh / 7.4 TWh.

I think you're off by a factor of 1000 somewhere in your math. You're looking at ~the output of a large nuclear plant, not 1000 of them.

Or my math is wrong. That's entirely possible too.

Re: Big water cutbacks ordered amid Colorado River shortage

#33

Post by JumpCrisscross »

joshuaheard wrote: post #28

Too bad the California Coastal Commission just denied the permit for a desalinization plant in Huntington Beach at the site of a decommissioned steam plant and reusing some of its infrastructure. It would have provided water to several Southern California cities. https://californiaglobe.com/articles/california-coastal-comm...

> would have provided water to several Southern California cities

It blows my mind that it's simpler to build, in one of the most water-blessed parts of our planet, a desalination plant, than it is to get farmers to quit growing literal fodder. Eighty percent of California's water goes to agriculture. Eighty percent.

Re: Big water cutbacks ordered amid Colorado River shortage

#34

Post by seadan83 »

bushbaba wrote: post #24
no_wizard wrote: post #3

Could we feasibly just run desalination stations from the coasts and pipe the water - like oil - to fill up these reservoirs? Setting cost aside for a second, is there any reason not to do something like this?

Why not pipe the water from the pacific northwest, similar to what was done with the Colorado river.

Lots and lots of mountains. On the east sides of the Cascades are massive dry and drought stricken areas (which are also farmland too). This same question can be asked about simply piping water from one side of the cascades to the other, let alone to the central valley

Re: Big water cutbacks ordered amid Colorado River shortage

#35

Post by [deleted] »

swatcoder wrote: post #29
ar813 wrote: post #10

The answer to this problem lies here: “Entsminger pointed out that roughly 80% of the river’s flow is used for agriculture, and most of that for thirsty crops like alfalfa, which is mainly grown for cattle, both in the U.S. and overseas.” The simple solution would be to raise prices on water such that it disincentivizes growing water hungry crops than alfalfa for example. The west’s water crisis is less about cities…

> The simple solution > The obvious answer This community seems like its at its best when it expresses humble curiosity and its worst when it shuts the door on learning by oversimplifying deeply complex matters as though nobody else had the sense to look straight at them. Water rights carry a legacy of centuries of personal and political history and thousands of competing interests. The levers with which to control p…

[deleted]

Re: Big water cutbacks ordered amid Colorado River shortage

#36

Post by vwoolf »

jmyeet wrote: post #6

At least this article notes that the vast majority of water usage is agriculture. This isn't something cities could or should solve by switching to (expensive) desalination to effectively subsidize agriculture. Most notably, alfalfa is mentioned here as farmers are going to have to switch to less water-intensive crops. Decreasing alfalfa production may well impact the ability to feed cattle. In the short term, that's…

The desalination plant solutions a "let's do both." https://californiaglobe.com/articles/california-coastal-comm...

Charge market prices for water and build desalination. Create abundance.

Re: Big water cutbacks ordered amid Colorado River shortage

#37

Post by vwoolf »

MengerSponge wrote: post #25

How the West was Lost: In America’s first climate war, John Wesley Powell tried to prevent the overdevelopment that led to environmental devastation. https://www.theatlantic.com/ideas/archive/2018/09/how-the-we...

Back then they didn't have good desalination technology. Now we do, and, while Israel is a leader, they export: https://www.scientificamerican.com/article/israel-proves-the...

Re: Big water cutbacks ordered amid Colorado River shortage

#38

Post by ericbarrett »

jmyeet wrote: post #6

At least this article notes that the vast majority of water usage is agriculture. This isn't something cities could or should solve by switching to (expensive) desalination to effectively subsidize agriculture. Most notably, alfalfa is mentioned here as farmers are going to have to switch to less water-intensive crops. Decreasing alfalfa production may well impact the ability to feed cattle. In the short term, that's…

I drove into Sacramento last year in late summer. There are flooded rice paddies just outside the city. Rice paddies! In California! In the middle of a historic drought!

Re: Big water cutbacks ordered amid Colorado River shortage

#39

Post by swatcoder »

no_wizard wrote: post #3

Could we feasibly just run desalination stations from the coasts and pipe the water - like oil - to fill up these reservoirs? Setting cost aside for a second, is there any reason not to do something like this?

We call them “desalination” plants, but the salt doesn’t just disappear. The more fresh water you have them produce, the more salt (brackish water) you need to manage as well.

So even while you may imagine the ocean as a limitless supply of water, there’s only so far you can scale desalination.

Re: Big water cutbacks ordered amid Colorado River shortage

#40

Post by khuey »

Syonyk wrote: post #21
no_wizard wrote: post #3

Could we feasibly just run desalination stations from the coasts and pipe the water - like oil - to fill up these reservoirs? Setting cost aside for a second, is there any reason not to do something like this?

I mean, if you don't care in the slightest about cost of the plants, the energy required, the land needed to run the giant tunnels... maybe? It's probably technically possible within the constraints of "I have a full country's resources available and can demand they be used to satisfy my absurd requirements and won't face huge blowback for using resources this way." But you can pencil it out. Cuts next year are 2-4 m…

40k gallons per second is on the order of the capacity of the Edmonston Pumping Plant of the State Water Project, so it's likely doable with existing technology.
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