Lake Mead at "inactive pool" - Hoover Dam and climate change

[Esquire]

Just to humor me, would you mind taking a stab at a numerical estimate? We can roll up all outdoor residential use if you like, that's probably easier to get data on.

I think Jub did a better job of this than I could have.

Thanks to Jub for doing the legwork.

I'll admit that I suspected something like that figure would emerge, based on similar calculations I've seen done for California. Do you still think a lawn sprinkler ban is terribly important and/or effective, given the absolutely trivial amount of water involved compared to other draws on the supply? If so, why? Especially given that apparently doesn't provide split numbers for indoor vs. outdoor usage, and that indoor usage is almost entirely recovered for tiny marginal costs since the relevant plants are already built.

[Jub]

Thanks to Jub for doing the legwork.

I'll admit that I suspected something like that figure would emerge, based on similar calculations I've seen done for California. Do you still think a lawn sprinkler ban is terribly important and/or effective, given the absolutely trivial amount of water involved compared to other draws on the supply? If so, why? Especially given that apparently doesn't provide split numbers for indoor vs. outdoor usage, and that indoor usage is almost entirely recovered for tiny marginal costs since the relevant plants are already built.

It's still worth doing as any water that can stay in the reservoir helps keep more water in the reservoir and the further upstream you curb the usage the better that is for both the reservoir and the ecosystems that depend on the river. It's still a bandaid, and possibly one that doesn't help terribly much but it's something easy to implement and enforce and it costs nothing to do it.

[Zaune]

Quite. And something else to consider is that if the state government makes the water companies cut off or ration water for crop irrigation right now, that might solve the water shortage but it will put a lot of people out of work and drive up food prices because of the inevitable crop failures. It might come to that anyway, but it's worth trying less drastic measures first.

That said, the current situation is not sustainable in the long run, and some pretty severe restrictions on how much water farms can draw on need to happen at some point. But if possible it'd be better to bring those rules in before the start of the planting season so farmers can plan around them.

[LaCroix]

This is one thing that people have been pointing out since probably a hundred years, have been becoming a problem in the last 50 and only in the last 10 years ordinary people were starting to notice it on a larger scale. Politics will take another 20 until they acknowledge it, most likely.

Some facts - the colorado compact water distribution "i call dibs" system for the colorado river is using rights to 15 million acrefeet of water.
This is problematic, because the river only has like 12 million in it, at most... So they decided to use all the water before it runs off to a place that doesn't need it, like... Mexico, and then added some immaginary water to their calculations that they just hope will manifest, even though it never did.
They made up by pumping ground water to an extent that would make Alaska Barbie blush like a prom girl, to the point that there are areas deflating like a flat tire with all the aquifiers collapsing after being emptied. There are hare-brained ideas to make up for water, I think we had a thread of a missisippi-colorado river diversion pipeline here on the forum a few years ago - next thing will probably be a fleet of helos flying in ice cubes from the arctic to place in Lake Mead to melt or something even more monumentally stupid.

Big part of the problem is the general policy of these water rights - use it or loose it - if farmers were to use less intensive crops, their share to use would shrink accordingly and eaten up by someone else further down on the list, meaning they never get back if they once use something less needy - they are pretty much forced to plant rice in order to make sure their water rights are not cut down permanently. Stupid system, there have been noises to reform it, but those noises have been going on for years without much change.

Big problem is the development of golf courses and water parks in that area - who ever fucking approves of these developments in a fucking desert is a lunatic - but then - the Utah governor asked for people to unite in prayer fo more rain, afaik, so...

Fun fact is that Vegas is actually a frontrunner in conservation, reducing use massively even while growing by huge margins - the famous dancing fountain, for example uses salt water not useful for anything else, and less of it than a few football fields of crops would use...

But the biggest problem is that people still cal it a drought - a 22 year period is not a drought, it is desertification. You can't hope to just sit it out and it will get better, you need to act, drastically...

[EnterpriseSovereign]

20+ years is defined as a megadrought. Western ‘Megadrought’ Is the Worst in 1,200 Years.

The searing “megadrought” that has gripped the southwest U.S. for more than two decades is the driest 22-year period in at least 1,200 years. The region hasn’t seen a more severe drought since the start of the scientific record around the year 800, according to new research published yesterday.

An exceptionally dry year in 2021 helped break the record. Before last year, a previous megadrought occurring in the late 1500s was the only other drought known to be worse than today. A megadrought is typically defined as a severe dry period lasting at least a couple of decades.

The current event has been strongly influenced by human-caused climate change, the study said. In fact, without the influence of global warming, today’s conditions probably wouldn’t be classified as a megadrought at all.

“It probably wouldn’t even be a continuous drought,” said Benjamin Cook, a NASA climate scientist and a co-author of the new study, published in Nature Climate Change. “We still would have had a drought. It still would have been reasonably bad. But it would be nowhere near the record-breaking event that we’re seeing right now.”

The new research, led by Park Williams of UCLA, is an update to a previous study published in 2020. That study, also led by Williams, examined the 19-year period between 2000 and 2018, comparing it with other historical droughts known to have occurred across the southwestern U.S.

“2021 was a pretty exceptional drought year out west,” said Cook, who was a co-author on the previous study as well. “And 2020 was pretty dry too. So it seemed like this drought was kind of continuing, so we decided to kind of do an updated assessment.”

These conditions have contributed to ongoing water woes across the Western states. Lake Mead and Lake Powell—two of the country’s largest reservoirs that provide water for millions of people—both reached record low levels in 2021. The federal government declared a water shortage at Lake Mead last year for the first time in the reservoir’s history.

In a statement released yesterday, Rep. Melanie Stansbury (D-N.M.) cited the new research in support for stronger climate action, including a call to pass the climate investments in the stalled “Build Back Better Act.”

“The science is clear and confirms what New Mexico’s communities have been experiencing for decades—climate change is here, and our water systems are ground zero,” she said.

In the previous study and its update, the researchers relied on analyses of ancient, preserved tree rings, which can provide information about the climate conditions over the course of the tree’s life. These tree ring records stretch back all the way to 800.

The previous study found that the current megadrought was the second-driest period in the record. Only one other event, occurring in the late 1500s, appeared to be worse.

Now, the updated research concludes that the last couple of years have pushed things over the edge. Soils across the Southwest were exceptionally dry in 2021. That’s despite abundant rainfall over the summer in some parts of the region.

As a result, the ongoing megadrought has stolen the record—and it’s probably not over yet.

The researchers also used an ensemble of climate models, which allowed them to make projections about the region’s climate future. The current drought has lasted 22 years so far, and the study finds that it’s highly likely—with a probability of around 94 percent—to last at least another year. And factoring in the continued influence of global warming over the next decade, it has a relatively high chance of breaking 30 years total before it finally ends.

Other studies suggest that more megadroughts are almost certain to follow.

Cook recently led another study on the likelihood of future megadroughts across the Southwest. The research finds that the odds of these events are rising alongside global temperatures. Even relatively modest warming is associated with at least a 50 percent chance of another two-decade megadrought by the end of the century.

Still, the research concludes, the odds are significantly higher with more extreme levels of future warming. Climate action still makes a major difference.

In the meantime, the Western states should brace for the possibility that the current drought will stretch on for at least a few more years.

“For the drought to end this year or next year, we’re gonna need one or two winters of pretty solid, above-average precipitation to kind of dig us out of the hole we’re in,” Cook said. “And maybe it’ll happen. But looking at historical variability, it’s unlikely.”

[Broomstick]

It makes far more sense to kill water to the vegas water shows, water-intensive cash crops, and other purely capitalist wastes of a precious resource even if lawns, personal swimming pools, etc. are also wasteful.

Vegas recycles some absurdly high amount of its water (claims are as high as 95% or higher) and the water shows actually utilize treated waste-water. In other words, the water shows in Vegas are refined sewage. They do lose some to evaporation, but the water shows actually are NOT a big loss of water. Arguably, they are part of aerating the treated waste-water.

The big "waster" of water really is agriculture. 75% of the water that is taken from Lake Mead goes to irrigation. Agricultural water use in the area is three times all other uses COMBINED. It is pointless to attempt conservation measures on other uses if you don't address the biggest one first. Indeed, if you could halve agricultural use you might well avert the current crisis (future crisis may or may not be an issue if the climate keeps drying out in the region).

No matter how well they do under desert sunshine we should NOT be growing water-intensive crops in the desert. Almonds and rice are the first two that come to mind, but also a lot of fruits and some vegetables. We don't have to abolish ALL agriculture in the region (at least not at present) but we really do need to curtail it. Especially if we want to retain the ability to generate hydropower on the Colorado and other river systems.

[Broomstick]

Quite. And something else to consider is that if the state government makes the water companies cut off or ration water for crop irrigation right now, that might solve the water shortage but it will put a lot of people out of work and drive up food prices because of the inevitable crop failures. It might come to that anyway, but it's worth trying less drastic measures first.

The rate the Colorado is dropping it's not going to be "the water companies" cutting off the supply, it's going to be Mother Nature, who is a LOT harder to negotiate with than human-run utility companies.

[Broomstick]

There are hare-brained ideas to make up for water, I think we had a thread of a missisippi-colorado river diversion pipeline here on the forum a few years ago - next thing will probably be a fleet of helos flying in ice cubes from the arctic to place in Lake Mead to melt or something even more monumentally stupid.

Actually, they usually float a notion of sucking water from the Great Lakes before they suggest flying in icebergs from the Arctic.

A Great Lakes diversion is not going to happen. First, it makes no sense from an engineering viewpoint. With a hypothetical end-point of Las Vegas (because why not) you'd have to transport water 2500 km (as the crow flies) horizontally and 425 meters vertically - nearly half a kilometer! - to get the water to Vegas. Even if someone was willing to supply the materials needed, the power costs would be prohibitive I'd think. Second, there's a shit-ton of international treaties and rules about taking water from the Great Lakes, the primary one being that if you take water out you must treat it and return it - which is strictly applied, much to the chagrin of some communities in my area that are juuuuuuust a bit outside the natural watershed.

[Jub]

It makes far more sense to kill water to the vegas water shows, water-intensive cash crops, and other purely capitalist wastes of a precious resource even if lawns, personal swimming pools, etc. are also wasteful.

Vegas recycles some absurdly high amount of its water (claims are as high as 95% or higher) and the water shows actually utilize treated waste-water. In other words, the water shows in Vegas are refined sewage. They do lose some to evaporation, but the water shows actually are NOT a big loss of water. Arguably, they are part of aerating the treated waste-water.

The big "waster" of water really is agriculture. 75% of the water that is taken from Lake Mead goes to irrigation. Agricultural water use in the area is three times all other uses COMBINED. It is pointless to attempt conservation measures on other uses if you don't address the biggest one first. Indeed, if you could halve agricultural use you might well avert the current crisis (future crisis may or may not be an issue if the climate keeps drying out in the region).

No matter how well they do under desert sunshine we should NOT be growing water-intensive crops in the desert. Almonds and rice are the first two that come to mind, but also a lot of fruits and some vegetables. We don't have to abolish ALL agriculture in the region (at least not at present) but we really do need to curtail it. Especially if we want to retain the ability to generate hydropower on the Colorado and other river systems.

Yeah, I ended up doing some extra digging and found that Vegas actually does well with water and that it's California agriculture that's to blame on this one.