Comment by notepad0x90
3 days ago
Looking at what Tehran is facing (not related to the war, water shortage), I'm wondering why california isn't investing in more desalination for SoCal, especially for LA.
I see some here:
https://lynceans.org/all-posts/status-of-desalination-plants...
But there are only a few in SoCal and they're for smaller communities like carlsbad or santa barbara. So it is there and it is working for some, why not more? naturally i assume it's because everything costs more at the coast.
> I'm wondering why california isn't investing in more desalination for SoCal, especially for LA.
Because California has plenty of water for residents. What California doesn't have is plenty of water for agribusiness.
And the agribusinesses do NOT want people paying close attention as all the valid solutions to water problems are basically "shut down agribusinesses in arid areas".
people are always trying to conserve water, and droughts have been a plague for the past few decades. Even if the agriculture is taking up all the water, it doesn't change how water scarcity is a a very real part of socal life. You don't have to shutdown agriculture elsewhere, and it is a vital part of california's economy, that's just a lazy solution. I can get behind getting the agriculture industry to finance partly the desalination plants so they can free up the fresh water via the aqueduct.
In the unlikely event california becomes independent, water rights will be a big deal too, those natural water sources won't be so reliable without nevada's cooperation.
> You don't have to shutdown agriculture elsewhere, and it is a vital part of california's economy, that's just a lazy solution.
Agribusiness is under 2% of the California economy and an even smaller employer. You could wipe it completely out and the state would barely notice.
And nobody is saying to wipe out actual food production. Mostly people want to stomp on things like growing and exporting alfalfa (which is effectively exporting water for all intents and purposes).
> droughts have been a plague for the past few decades
Droughts have been a plague forever. Quoting Steinbeck from East of Eden:
“During the dry years, the people forgot about the rich years, and when the wet years returned, they lost all memory of the dry years. It was always that way.”
> In the unlikely event california becomes independent, water rights will be a big deal too
This is all hypothetical of course but the logical eastern border of an independent state centered in what's now California would be near Denver for precisely this reason.
Because the economics of desalination require locking in long term purchase/production rates at prices that dwarf current and other sources of water. SD's Poseidon desal is projected at ~$3.7k per acre ft for 2026 whereas SDCWA SWP water is ~$1.5-1.9k acre ft. Leak fixes, groundwater recharge, local aquifers, water banking, potable reuse, etc. are all more economical means of bolstering water supply.
A big factor in determining desalination placement in the region are the groundwater basins. Limited size and availability makes the case for desalination as means for resiliency. Another is that situating adjacent to power plants so as to use their already coastally degraded intakes/outfalls. Doheny is to use subsurface slant wells for intakes, but it's also lower output too.
As for LA. they're working on getting their potable reuse plants/projects up and running. The largest indirect potable reuse plant in the world has been operating in OC for ~18 years. Lower operating costs than desalination, reduced wastewater discharge, and reduced coastal impact.
that's very insightful. But if I can dive a bit deeper, why can't desalination be made at a grander scale? why aren't desalination plants trying to fill up artificial lakes for example, where those lakes are also being topped-up with reused potables. Would it help if there were much larger nuclear powerplants in the desert that take in salt water via an aqueduct from the sea and send back fresh water to artificial lakes, depositing the waste into the desert? Salton sea might be a good enough spot in socal for example, where it is already toxic and salty.
The few times I've been to the Salton area, I was amazed at the agriculture in the middle of the desert, including things like citrus plants, despite smelling the stench of salton from there. There are various lakes that dry up all the time like big bear, what would it take to keep such basins capable of sustaining fresh watter topped up with desalinated fresh water, instead of directly consuming it? In other words, making desalination an upstream element, with the goal of resisting drought overall, not just immediate fresh water supply.
I've ever wondered about places like death valley, if the elevation there is so low, is it easier to build geothermal plants that could desalinate at a greater rate there?
And since I'm asking dumb questions already, if an aqueduct to LA is possible at a 4 hour driving distance, then I know it would be costly, but is it that impractical to build an aqueduct from the great lakes, which have no shortage of fresh water, and evaporation loss could easily be recouped by the sheer volume of available fresh water supply.
The Owens River source for LA is so good because it’s basically a continuous gradual decline from the source to the city, requiring no pumps.
Pumping is very energy intensive. At around 2000-3000 ft the energy needed to pump fresh water starts to equal the energy needed to desalinate the same amount of salt water.
Even if it’s just going up then back down again like the Tehachapi Mountains only like 1/3rd of the energy can be reclaimed.
There are environmental and financial concerns https://calmatters.org/environment/2022/05/california-desali...
I don't understand the financial concern at all. How could increasing the water supply increase the price? It only makes sense to me if the price is artificially low right now.
Environmental damage by a desalinization plant couldn't possibly be worse than overdrawing the acquifer -- the defacto solution.
As part of the contract for construction, the county or city must buy a certain amount of water every year.
Because desalination is not economically feasible, the water is more expensive and this extra subsidy raises the cost of the water bill.
This is how it works for the facility in San Diego County.
Building a desalination facility is economically hard to justify because the break-even point seems far away. It also assumes the state won’t eventually create a state-wide solution, which would benefit from a state-level economy of scale that a city/county effort might not.
> It also assumes the state won’t eventually create a state-wide solution, which would benefit from a state-level economy of scale that a city/county effort might not.
How would a state-level solution to who deserves water more benefit from economies of scale? This is about as core of an example of where you don't want central planning as you can find.
Building an industrial facility in california is much more difficult and expensive due to numerous regulations.
Water is normally "free" from mother nature. Desalinated water is not free as it cost energy to get the clean water. Even if there's a pump to get water from aquifers into the water system, that still rounds to free compared to the cost of running a desalination plant.
That is why I said "artificially low." As there is a water shortage, the current price should justifiably be higher. Instead we will simply run out or damage the acquifer by saltwater intrusion.
I’m in a rare community in Southern California (part of north county San Diego) where my water is 27% from the ocean (10% for rest of San Diego county).
It’s cool. Still totally hard and makes everything fail early.
The US needs a national water grid.
It would pay for itself after a few flooding events where were are able to redistribute the water more quickly. It also provides clean energy storage.
I've posted about it before with links to the studies but it usually just starts an argument by people worried the rest of the country is going to steal their water...
It seems like the least efficient way to solve the problem. Theres lots of water in many places in the US, if water is just allowed to be priced by how scarce it is in California, maybe people will move to a place where it’s not such a big deal.
This is the sort of low quality reply that made me think twice about commenting. Every time I mention it it's another set of poor quality, no thought, drive by responses and downvotes.
https://www.osti.gov/biblio/963122
Why do you think it's good to let the productive agricultural land of CA lay fallow? Why do you want areas in the east to go without proper flood control? Why do you think national food security is not a priority? I could go on... Read up on it if you like, or don't. Whatever.
2 replies →