Water security

[Dr Sardonicus]

Originally Posted by tServo

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I can't believe there are plans underway to build a couple of huge silicon fab plants in Arizona, of all places. What will they do when those multi billion dollar facilities stand empty due to no water.

IMO Intel is more likely to leave if/when their tax parasitism incentive provisions become less attractive. For example, they're getting an 80% discount on their property taxes.

[xilman]

Originally Posted by Dr Sardonicus

IMO Intel is more likely to leave if/when their tax parasitism incentive provisions become less attractive. For example, they're getting an 80% discount on their property taxes.

AKA The Golden Rule.

He who has the gold makes the rules.

[MooMoo2]

Originally Posted by Nick

Lake Mead: Largest US reservoir dips to record low
https://www.bbc.com/news/world-us-canada-57436860

Lake Mead has dropped another ~4 feet since that time. A few hundred miles upstream, Lake Powell (only a tiny bit smaller than Lake Mead) is expected to hit an all-time low within the next two days: https://lakepowell.water-data.com/

Down and down, and down it goes, and where it stops, nobody knows...

[Uncwilly]

"Record low" for those to lakes are being reported falsely. The first day that the water was allowed to build behind the dams was the record low.

But, did you expect it to go up during NHS (northern Hemisphere Summer)? Why do you think that cities are making long term major plans for water like Los Angeles did in the 190x's? At that time voters agreed to a bonds that were larger than the value of the City government's holdings. https://waterandpower.org/museum/Con..._Aqueduct.html

[MooMoo2]

Originally Posted by Uncwilly

"Record low" for those to lakes are being reported falsely. The first day that the water was allowed to build behind the dams was the record low.

Yeah, it should have been "record low since the dam reached capacity". Kind of like how M51 is not the largest prime; just the largest known prime.

But, did you expect it to go up during NHS (northern Hemisphere Summer)?

I thought that Mead's decline would stop (monsoon runoff).

Edit: just looked up the averages for Powell. It typically reaches a low for the year in mid-April, just before most of the snowpack in the Rockies starts melting. The yearly high is usually in early July, after most of the melting is complete. So there's quite a large drop left before Powell starts rising again.

[Dr Sardonicus]

Western states face first federal water cuts

WASHINGTON (AP) - U.S. officials on Monday declared the first-ever water shortage from a river that serves 40 million people in the West, triggering cuts to some Arizona farmers next year amid a gripping drought.
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States, cities, farmers and others have diversified their water sources over the years, helping soften the blow of the upcoming cuts. But federal officials said Monday's declaration makes clear that conditions have intensified faster than scientists predicted in 2019, when some states in the Colorado River basin agreed to give up shares of water to maintain levels at Lake Mead.

"The announcement today is a recognition that the hydrology that was planned for years ago - but we hoped we would never see — is here," said Bureau of Reclamation Commissioner Camille Touton.
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Water stored in Lake Mead and Lake Powell is divvied up through legal agreements among the seven Colorado River basin states, the federal government, Mexico and others. The agreements determine how much water each gets, when cuts are triggered and the order in which the parties have to sacrifice some of their supply.

Under a 2019 drought contingency plan, Arizona, Nevada, California and Mexico agreed to give up shares of their water to maintain water levels at Lake Mead. The voluntary measures weren't enough to prevent the shortage declaration.
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In the U.S., Arizona will be hardest hit and lose 18% of its share from the river next year, or 512,000 acre-feet of water. That's around 8% of the state's total water use.

An acre-foot is enough water to supply one to two households a year.^†
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Farmers in central Arizona, who are among the state's largest producers of livestock, dairy, alfalfa, wheat and barley, will bear the brunt of the cuts. Their allocation comes from water deemed "extra" by the agency that supplies water to much of the region, making them the first to lose it during a shortage.
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^†This statement got my attention. An acre-foot is 43560 cubic feet, which is 325851.429 gallons. Dividing by 365, we find that an acre-foot per year is a bit over 892 gallons per day, or around 27154 gallons a month. Half that would be just over 446 gallons per day, or 13577 gallons per month.

[kriesel]

Originally Posted by Dr Sardonicus

This statement got my attention. An acre-foot is 43560 cubic feet, which is 325851.429 gallons. Dividing by 365, we find that an acre-foot per year is a bit over 892 gallons per day, or around 27154 gallons a month. Half that would be just over 446 gallons per day, or 13577 gallons per month.

An acre-foot is about equal to what falls on my home's lot annually. I'm sure I'm using far less than that. https://www.currentresults.com/Weath...cipitation.php

Further populating the drier US states with more millions annually crossing the border out of control isn't helping though.

[S485122]

Originally Posted by Dr Sardonicus

^†This statement got my attention. An acre-foot is 43560 cubic feet, which is 325851.429 gallons. Dividing by 365, we find that an acre-foot per year is a bit over 892 gallons per day, or around 27154 gallons a month. Half that would be just over 446 gallons per day, or 13577 gallons per month.

Translating to metric units an acre-foot is a bit more than 1223 m³ (cubic metres). With an USA average household size of about 2,5, this means a bit more than 1,3 m³ or 1352 litres per day per person (about 357 US gallons a day per person). Or half if one "acre-foot" is enough for 2 households.
Would that quantity include the water usage for agricultural needs ? It seems rather high. If it does include agricultural needs, that statement is not very enlightening : household seems to point to water used in a house an its garden (plus the water used outside the home for personal use.)

[Xyzzy]

According to our water bill, we use a little under 100 gallons a day. (Or ~33 gallons per person per day.)

So that figure probably includes other things.

[Dr Sardonicus]

It's hard for me to imagine using anywhere near 446 gallons of water per day apart from (a) having a significant leak on my side of the meter or (b) doing a lot of lawn and garden watering. For Arizona residents I would guess (b) is a major factor. It seems very wasteful to me, going to the effort and expense of processing large amounts of water to make it safe for people to drink, and then dumping it on the ground so that Kentucky bluegrass and other ornamental plants requiring lots of water will grow in arid or semi-arid regions.

One other thing that came to mind was residential swimming pools. They can lose a lot of water by evaporation. If a 400 square foot pool loses 2 inches per week by evaporation, that's an average of a bit over 71 gallons per day.

[kriesel]

It may be a per household share of all usage in the state; residential, agricultural, commercial, industrial, utility, government, ...
Per the USGS page, https://www.usgs.gov/mission-areas/w...otal-water-use the 3 biggest categories are "thermoelectric power", irrigation, and public supply. (Per https://www.usgs.gov/mission-areas/w...center_objects by "thermoelectric power" they mean fossil-fuel, nuclear, or geothermal electrical generation there; effectively, not wind solar or hydro)