15 July 2022 |

Desalination demoted in California

By Nick Van Osdol

If you live in Orange County, you may have followed the ongoing saga about the new desalination plant in Huntington Beach.

I was in Newport over the Fourth, walking on the beach with a friend. I saw what looked like an old power plant up north and asked what kind of power plant it was. This got us talking, and, as it turns out, that site is also the proposed location for a new desalination plant. Not knowing a ton about the state of desalination in California, I started to do some research.

Taking a look at the dynamics of desalination today will allow us to discuss a range of topics, from tensions between environmentalists and climate tech developers to baseload power 👇 

The download on desalination 

The West Coast has been experiencing a prolonged, severe drought for the better part of the past decade. There are numerous proposals regarding from where to drum up more water, ranging from refilling aquifers to sourcing water from the Mississippi River.

Desalination is another option. Desalination involves taking ocean or brackish water and, you guessed it, removing the salt (and other dissolved minerals). It’s an energy-intensive process that also produces brine, wastewater with salt and other pollutants. But it makes fresh water, viable even for potable use. 

The primary tech to desalinate water has shifted over decades, moving from membrane technologies to renewable energy in the present day. More than 16,000 desalination plants are operational worldwide, supplying 300 million people with fresh water. Saudi Arabia and UAE are world leaders in desalination by volume. Why have those countries invested more heavily in others in the technology? For one, they are among the countries with the highest water scarcity risk, projected out to 2040 and beyond. 

Water scarcity risk globally (red = worse)

For countries in the Middle East, there aren’t many other options available to level up their water security. But desalination isn’t easy either. Energy consumption is the largest line item for plants. Energy costs for desalination plants can be approximately 10x the cost of other water treatment plants – e.g., desalination can be 10x as expensive in energy terms as recycling water. 

Still, the tech has become much more efficient, and renewable energy has become much cheaper. As a quick gut check on whether desalination can make sense, charting the rise of global desalination capacity seems to suggest ‘yes.’

Growth in global desalination capacity

Stalling out in Socal

Let’s tie things back to California and Los Angeles county. South of LA, there’s already an operational desalination plant in Carlsbad, California, which can generate 50 million gallons of fresh water daily. Which is more than a quarter of the water all of San Diego county uses daily

The Carlsbad plant opened in late 2015. Considering its relative success, one might expect Socal to start scaling the tech and building more plants, especially considering the water shortages counties across the state face. 

There are several proposals for new plants. In Huntington Beach, the city has spent two decades waffling on whether to build one. Gavin Newsom is in favor of spending $1.4B to open the new desal plant in Huntington, with the potential to create 100 million gallons of water daily.

Poseidon Water, the leading desalination developer in the U.S., had gotten as far as seeking final approval from the California Coastal Commission to start building the plant. Just one hiccup – last month, the commission voted to reject the plan.

There are a number of reasons the commission cited, all of which are worth considering.  

For one, there are legitimate concerns about the wastewater these plants produce. Recent studies suggest the challenge of dealing with briney wastewater has been underestimated significantly

Secondly, desalination is more expensive than other options, like increasing water recycling rates. LA county only recycles 1% of its water right now. That’s a staggering tech and policy failure. The county has set a goal to increase this to 100% (or as close as possible) by 2035. Hard to say whether they will make sufficient, steady progress towards that goal

Thirdly, there are other environmental unknowns that interest groups raised red flags about, e.g., impacts on coastal marine life.

I’ll address each of these (again, valid) concerns one by one.

On the waste front, until you start scaling technologies like desalination, you don’t afford yourself a real opportunity to think critically and solve challenges surrounding the waste. Some companies are already thinking about reclaiming metals and minerals from brine, and others want to use existing wastewater flows for things like ocean deacidification. Waste challenges, whether in nuclear, or desalination, should be viewed as a secondary opportunity for recycling, reclamation, and exploring other solutions.

On the cost front, my stance for exploring the viability of new technologies will typically tend towards “yes, and.” LA should increase its water recycling rates drastically. And invest in a desalination plant to build redundancy and see if costs can come down over time. Studies in California almost a decade ago already posited desalination was becoming economical. I have to imagine the economics have improved further since then.

On the environmental front? This is one of the biggest challenges in aligning stakeholders around climate tech projects. Wind farms kill birds. Forestry projects can disrupt endangered animals’ habitats. I would point out that climate change has entered us into the ‘sixth mass extinction.’ Pragmatically, solving structural and global climate issues might benefit more species than shutting down solutions on a local, case-by-case basis.


You don’t scale and improve technologies by not building them in the first place. The portfolio approach is the best path forward for climate tech, considering how far down the global warming path the world already is. That means trying a bevy of different things. They won’t all work out. But testing and iterating on a basket of approaches help ensure there will be a handful of viable solutions at scale and sophistication (ideally, comparable to what solar has achieved) decades down the road. 

There are also hues of NIMBYism that color this story. Most people are excited about most climate technologies in concept. Often when you want to build something like wind turbines in local communities, however, that conversation gets a bit harder. This is a real problem for renewable energy developers, not just for things like nuclear power plants. And for other technologies like desalination. Again, this cuts back to stakeholder alignment. Presumably, the best lever would be encouraging folks to look at the big picture. Easier said and written than done. Hopefully, content & media can help.
Finally, things like desalination are a good impetus to think about the baseload power of the future. In a world where renewable energy sources provide abundant, cheap electricity, things like desalination become a bit more of a no-brainer. That’s a ways off, of course, but it offers another example of why investments in experimental tech, whether ‘supercritical’ geothermal, nuclear fusion, or other, are worthwhile.