A imaginative and prescient for the alleviation of water shortage within the US Southwest and the revitalization of the Salton Sea – Casey Handmer’s weblog

Simply a few hours drive east of Los Angeles lies the Imperial Valley, dwelling to Palm Springs, a number of the best agriculture on Earth, and the Salton Sea. Along with Los Angeles, this space makes use of over 5 million acre-feet (MAF) of water from the Colorado River yearly, a river whose circulate continues to development downward as a result of altering local weather.

For a few years, California’s strategy to the issue has been to hunt consolation from its senior water rights and its outsized energy in comparison with neighboring states, whereas telling tales of managed decline and fallowing farms in each the Imperial and Central Valleys. Few bear in mind the large public works tasks that constructed the dams on the Decrease Colorado a century in the past and introduced water a whole lot of miles throughout the desert, making life attainable for the tens of hundreds of thousands of people that now name it dwelling. These tasks had been visionary and we stand right here right now due to their embodied will to battle again in opposition to Holocene desertification.

The arrival of low cost photo voltaic provides us one other highly effective instrument to battle in opposition to the desert and to deliver life and water to large swaths of the western US, beginning with the Imperial Valley. In an earlier publish I wrote more generally about supporting rivers. Right here, I’ll focus on the outline of a specific project that may rework Southern California and its relation to water, vitality, and trade to be prepared for one more miracle century of development and wealth creation.

As we speak, a number of canals deliver water from the Decrease Colorado into the US a part of the Imperial Valley for irrigation. By treaty the final 1.5 MAF of the Colorado continues into Mexico, which additionally has vibrant agricultural exercise within the Colorado delta space close to Mexicali. The agricultural areas are, broadly talking, low mendacity and often flooded. The fashionable Salton Sea shaped in 1905 when an irrigation mishap diverted the Colorado into the sink, itself shaped by crustal extension and rifting. Its earlier incarnation Lake Cahuilla dried up round 1700.

The Salton Sea’s stage continues to drop as a consequence of evaporation, resulting in growing salinity (now too excessive to assist any fish, inflicting a number of nice die-offs within the early 2010s) and infrastructure challenges for communities that reside across the lake, along with extreme and widespread respiratory issues from mud from the uncovered lake mattress. Briefly, the Salton Sea is a blight, a festering environmental disaster and a supply of tolerating disgrace for California, a state that prides itself on environmental sensibility, wealth, and entrepreneurial spirit.

Nicely could it stay, since the price of desalinating the lake by itself is prohibitive and there are not any handy sources of water in its catchment by which to manage its stage.

This has now modified. Photo voltaic photovoltaic panels are, acre for acre, 100 occasions extra economically productive than farming. A comparatively small desert space adjoining to fields, as soon as developed for photo voltaic, can ship sufficient insanely low cost electrical energy that it could actually rework the financial system of your complete area.

Briefly, we have to construct a reverse osmosis desalination plant that backs up the pure circulate of the Colorado. A photo voltaic powered environmental restoration machine that alleviates intense ecological pressures and ensures water abundance for the southwest ceaselessly.

Not like the earlier century’s pioneering irrigation tasks, this type of growth requires no new expertise, merely the scaled software of current processes and merchandise at a stage that will barely have an effect on current provide chains.

That is the way it works.

A photo voltaic PV-powered RO desalination plant is constructed within the desert west of Yuma, handy to current irrigation canals and the Colorado river. It’s fed by a big sea water pipeline that runs down the flood plain throughout the border to the Gulf of California, and in addition by a separate spur line that pulls from the Salton Sea and runs parallel to the Coachella Canal.

RO desal splits the incoming ~3% salinity stream into two halves, one contemporary and one ~6% salinity. This concentrated brine is fed to adjoining brine processing amenities (ideally in each international locations) that exploit the area’s considerable photo voltaic and geothermal vitality to extract doubtlessly hundreds of thousands of tonnes of lithium, sodium, magnesium, chloride, and different metals present in sea water. The ensuing depleted brine is piped again to the ocean the place it’s completely combined with sea water and discharged.

The contemporary water is distributed into the area’s irrigation canals, enabling regulation of the Salton Sea’s stage in addition to its desalination, and the preservation of extra of the Colorado’s circulate into Mexico. The Coachella Canal passes inside a mile of the Colorado River Aqueduct, so this desalination system might doubtlessly additionally feed contemporary water into the Los Angeles municipal provide.

The challenge has a number of sources of income: water gross sales, brine merchandise, and land worth appreciation as soon as the Salton Sea as soon as once more turns into suitable with human habitation. Certainly, had been the lake stage tamed and restored to assist a various ecosystem, the excesses of agricultural exploitation remediated, I feel it will turn out to be corresponding to Lake Tahoe in aesthetics, however with a a lot stronger foundation of trade as a consequence of considerable vitality, water, and minerals.

This map exhibits the world of photo voltaic panels required to feed the RO and brine crops. It appears laborious to imagine that such a tiny nook of such an enormous desert, so removed from any roads that its existence could be unknown to all however a handful of airline passengers, could possibly be able to producing 5 MAF of contemporary water per yr – California’s whole Colorado River allocation! That is the facility of photo voltaic vitality! The adjoining agricultural areas develop crops that require water, planting, harvesting, fertilizers, pesticides, and the correct sorts of climate, all to seize the solar’s vitality within the type of digestible leaves, nuts, and fruits – at 0.01% the vitality throughput effectivity of photo voltaic.

Let’s take a better take a look at a block diagram exhibiting how worth accrues within the system.

The photo voltaic panels convert wasted daylight into electrical energy, one of the crucial helpful types of vitality, on the lowest value ever in human historical past. The batteries make this energy obtainable at evening, enabling 100% utilization of the upper capex programs downstream. The RO desal plant makes use of this energy to strip salt out of contemporary water, a remarkably environment friendly and excessive maturity expertise already deployed to the tune of greater than 30 MAF/yr, primarily within the Center East. At $1000/AF, this unit alone accrues $5b in annual income.

The brine plant is uniquely in a position to exploit increased concentrations of ocean ions, low cost warmth and electrical energy, and California’s burgeoning demand for important minerals. 5 MAF/yr of 6% salinity brine accommodates greater than 10 million tonnes of magnesium, corresponding to present world manufacturing, to not point out different gentle metals. At spot costs round $5000/T, a mature brine extraction trade might web >$50b/yr, which can assist to maintain the water low cost and meals plentiful. The brine plant may get well agricultural chemical compounds from the Salton Sea, together with nitrates and phosphates. Whereas nitrates are plentiful due to the Haber Bosch course of, phosphates are more and more scarce.

Lastly, the “waste” product is nothing greater than concentrated sea water, one thing anybody could make of their kitchen and which turbulent mixing with the ocean can successfully dilute, nullifying affect on the consumption and return.

Ten years in the past, photo voltaic was too costly to make this attainable. That’s not the case. The world deployed about 450 GW of photo voltaic in 2023, and for the primary time vitality value not dominates the price of desalinated water. In different phrases, we are actually within the age of water abundance.

California ought to unabashedly exploit its mature industrial sector and visionary environmentalism to quell the rising water shortage disaster, mend fences with Mexico, construct native trade, bolster agricultural manufacturing, restore the Salton Sea, construct new shining cities alongside its shores, and flaunt its unequaled excellence by exporting alfalfa to all corners of the globe.