The recent suggestion by a Democratic candidate in the recall election, Kevin Pallfrath, to build a huge freshwater pipeline from the Mississippi River to California reminded me that there hasn’t been an announcement of new technologies for increasing freshwater supplies on the front page in a long time. That’s why a recent article in a professional journal from some researchers in Korea stood out. These researchers discovered a clever way to make a membrane to distill seawater faster and cheaper.
Clearly, climate change is going to mess up the distribution of water supplies around the globe, especially creating extended droughts in areas that formerly had a decent water supply—like California. That will create a push to “do something”, and building a 2000-mile pipeline is probably not the right idea. Lots of steel, lots of pumping stations, lots of right-of-way. Water conservation and stopping leaks have gotten lots of attention, but that is different for actions to increase the supply.
What does make sense is to come up with better ways to desalinate seawater. Most of the populations affected by the new severe, recurring droughts are within 100 miles of a seacoast. Desalination costs have been improving, slowly, mostly for the high-pressure reverse osmosis technologies. The best prices I have seen put the cost of fresh water from the sea at $2.50 to $3 per thousand gallons from the dozens of desalination plants now installed worldwide. See this article for details. That is a far cry from the $50/acre-foot (15 cents per thousand gallons) for water from the State Water Project—when it is available. Water from Federal projects is even cheaper when it exists. The complications of western water law prevent the price of water from being rationalized in a market, so buyers are stuck paying wildly different prices for it and fighting bitterly over the cheap supplies. The hope has been that desalination costs would fall below $1 per thousand gallons and narrow the differential.
While incremental improvements continue, there has not been the dramatic ten-fold reductions in costs that have occurred with solar panels, wind turbines, and batteries. (See this great recent “deep dive” from CleanEdge on these trends.) Some of the lesser success might be due to lack of sustained attention, since rain begins to fall every once in a while and people quickly ignore the persistent problem. Every year we take more from rivers and underground aquifers than can be sustained and now more frequent and severe droughts compound the problem. Are we not spending enough on R&D? Maybe. Are we not providing subsidies to incentivize innovation? Maybe. The increasing global water shortage may force more of these kinds of actions and create some breakthroughs. It is a field relatively wide open to creative minds, but getting much less government attention than renewable energy. Look for that to change as the seriousness grows and look for government to throw a lot more money at this.