From the comments, but worth elevating to a post so folks it doesn’t get lost – Tom McCann on Arizona Sen. Martha McSally’s bill to restart the Yuma Desalting Plant:
McSally’s bill is nothing more than a PR stunt–a way to appear to be doing something on the Colorado River without any risk of it actually happening. If she had talked to anyone knowledgeable about the Yuma Desalting Plant (doubtful), she would know that the plant cannot be operated without extensive repairs and capital improvements, which Reclamation estimated nearly a decade ago would cost anywhere from $160-450 million, plus another $25-40 million in annual operating costs. That’s never going to happen. The YDP, as originally designed and intended, is dead.
But there are other, far less expensive ways to satisfy the US obligations under the 1974 Salinity Control Act and Minute 242, conserve water in Lake Mead AND preserve the environmental values of the Cienega. In 2013 we described one such alternative: construct a pipeline to transport the 100KAF Wellton-Mohawk drain water to Imperial Dam where it would be mixed with roughly 6MAF of Colorado River water that passes that point every year, eliminating the need to release an additional 100KAF from Mead every year. At the same time, the US could increase pumping from the 242 well field and dedicate 50 KAF/yr of that water to the Cienega. The total cost of that alternative was estimated at around $100 million, which would be funded by non-federal parties in return for ICS credit, with an annual operating cost of about $4 million–less than Reclamation spends today to NOT operate the YDP.
Unfortunately the proposal never got any traction because entities that take their Colorado River water from Imperial Dam objected to the 20-30 ppm expected increase in salinity there, despite the fact that (1) 20-30 ppm is within the normal variation of salinity at Imperial and (2) the salinity at Imperial today is far less than it was in the past (less than 700 ppm in recent years), largely through the work of the Title 2 Salinity Control Program to which those water users do not contribute.
Bless McSally for having the courage to at least do something. While everyone fiddles and naysays, reservoirs on the Colorado continue to drop, along with the future of the Southwest……
I think there is more to the story of the Drain Water Interceptor Project than described above. Raising salinity for farmers and citizens at the end of the River, not within normal variation, but in addition to, is a political nonstarter. Farmers will see crop yields decrease, permanently Citizens of California, Arizona and Mexico will be forced to drink saltier water, permanently. Meanwhile, everyone else gets the same water as before. Hardly seems fair. That may be why the Interceptor Project got no traction. One can certainly see why parties upstream of Imperial Dam would be willing to pay, they’re not stuck with the downside.
Regarding the Yuma Desalting Plant, the facts found online don’t agree with the narrative above. According to the Bureau of Reclamation’s report on the last time the YDP ran (2012, see following link: https://www.usbr.gov/lc/yuma/facilities/ydp/YDPPilotRunFinal072712.pdf)
CAP, MWD and SNWA paid the Bureau to run the plant for a year or until 29,300 acre-ft was conserved. The Yuma Desalting Plant finished the run ahead of schedule and under budget, while maintaining flows to the Cienega through cooperative actions between the US, Mexico and NGOs.
In the same report, Reclamation lists projects necessary for sustained operation of the Yuma Desalting Plant. Its estimate for these projects in 2012 dollars is $55MM. This is nowhere near the numbers presented above. Even if the numbers listed above are accurate, a very big if, they are still way below what California spent to build the Claude “Bud” Lewis Carlsbad Desalination Plant in Carlsbad, CA, which only has half the capacity of the YDP. Wikipedia lists the cost of that plant at $1 Billion. The YDP sounds like a bargain by comparison.
Based on these facts, the YDP sounds like a viable option, of many, the people and entities of the Southwest need to consider in dealing with this seemingly permanent drought.
A few facts:
1) Salinity. Salinity above Imperial Dam was 834 mg/l in 1974 when the Colorado River Salinity Control Act was enacted. Title II programs have successfully reduced that to less than 700 mg/l today. Salinity above Imperial has ranged from 671 mg/l to 726 mg/l since 2000. See: https://www.usbr.gov/lc/region/g4000/NaturalFlow/HistoricalSLOAD_2018_20200110.xlsx. The Salinity Control program is paid for by upstream users, even though those that take their water from Imperial have benefitted substantially.
2) YDP Pilot Run. The plant ran at 1/3 capacity during the pilot run, which was the maximum capacity possible given the few remaining membranes and Reclamation’s concern about leaks in the failing aluminum-bronze piping throughout the plant. After the pilot run concluded, I understood that Reclamation only had sufficient membranes left for perhaps 6 months of further operation at 1/3 capacity. The membranes used at YDP are a non-standard size, old technology, and not generally available today.
3) YDP Continued Operation. In conjunction with the pilot run, CAP, SNWA and MWD sponsored a separate research effort at Reclamation’s Water Quality Improvement Center to evaluate alternative pre-treatment and membrane technologies that could be employed at the YDP. Ten different alternatives were considered. From my notes, the capital cost to implement those alternatives ranged from $137 to $430 million, with operation and maintenance costs ranging from $25 to $40 million per year. Reclamation has apparently chosen not to include that study report on its website.
4) YDP vs. Carlsbad. Ocean water is about 15 times saltier than the WMIDD drain water, and ocean desalination is always far more expensive than brackish desalination. In addition, a significant portion (perhaps half) of the cost at Carlsbad relates to unique environmental requirements for that plant. Regardless, the United States has no intention of funding either capital improvements or annual operating costs for YDP, and McSally’s bill does not seek that.
Finally, it must be remembered that operating the YDP would not produce ANY additional water for Colorado River users. It would, however, avoid the loss (theft?) of more than 100KAF of extra water that Reclamation currently takes from Mead every year to Arizona’s detriment.