Los Angeles Wants to Use the Hoover Dam as a Giant Battery. The Hurdles Could Be More Historical than Technical

Los Angeles is looking into whether it should spend an estimated US$3 billion on a massive, 20-mile underground pumped hydropower storage system that would be connected to the iconic Hoover Dam on the Colorado River outside of Las Vegas.

If it does get built, this system would essentially serve as a giant battery to store power.

Having written a book about the aggressive propaganda program behind the Hoover Dam’s construction in the 1920s and 1930s, I can say that the technical and financial challenges of this plan are sure to pale in comparison to the legal and political roadblocks that will have to be overcome.

Among the biggest obstacles are the long-running fights over the Colorado River and its water, and that the Colorado is a shrinking river due to climate change and long-term drought.
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More considerations
Proponents of the Hoover Dam battery concept say it would be an environmentally friendly way to generate more electricity without using fossil fuels.  Yet there are more considerations here, too.

First, the project calls for nearly 20 miles of new underground pipes to run from below the dam back into Lake Mead.  The water that it takes to fill those pipes along with the water that is circulated in perpetuity will take some coveted Colorado River water permanently out of the downstream flow.

Second, the time hardly seems right.  The Colorado is in decline.  With climate scientists predicting that the volume of water in the Colorado River will continue to decrease, states that rely on the river are bracing for potentially drastic cuts to water supplies.

Read more at Los Angeles Wants to Use the Hoover Dam as a Giant Battery.  The Hurdles Could Be More Historical than Technical