Expand solar development in the desert, not San Joaquin Valley farms

Successfully coping with severe droughts in California and the Southwest requires tough choices, all of them expensive and none of them perfect. But taking millions of acres out of cultivation and replacing them with solar farms is not the answer.

California produces over one-third of America’s vegetables and three quarters of the country’s fruits and nuts – more than half of which is grown in the San Joaquin Valley. According to the California Farmland Trust, the San Joaquin Basin contains the world’s largest patch of Class 1 soil, which is the best there is. 

Putting solar farms in more than a small fraction of this rich land will not only displace farming, but have a heat island impact in the enclosed valley. That would be unhealthy for the farms and people that remain, and could even change atmospheric conditions over a wide area, worsening the drought.

If new solar farms are destined to carpet hundreds of square miles of land, they should be dispersed throughout the state and near already existing high voltage lines. Or, they should be concentrated in California’s abundant stretches of uninhabited land such as the Mojave Desert. 

With food shortages worsening throughout the world, Californians should be focusing on how to preserve agriculture in the San Joaquin Valley. Why, for example, are spreading basins being proposed to allow runoff from atmospheric rivers to percolate when flood irrigation used to replenish aquifers while also growing food? Why isn’t that practice being evaluated and supported wherever appropriate?

Much of the depletion of groundwater aquifers that led to passage of the Sustainable Groundwater Management Act was caused because farmers had their allocations from rivers reduced, which forced them to pump more groundwater to irrigate their crops. Drought was a factor, but cutbacks in surface water deliveries and the abandonment of flood irrigation is what made groundwater pumping unsustainable.

The motivation to protect ecosystems during a drought is commendable. But there are solutions that don’t have to destroy the agricultural economy on what is the richest farmland in the world. Some of the environmentalist goals, such as maintaining a year-round flow in the San Joaquin River, have no precedent in history. 

When there were severe droughts, that river often dried up in the summer.

Recognizing this highlights a larger reality. The civilization we’ve built has permanently altered nature, and returning it to a pre-civilization state is not an option. For example, because we suppress natural wildfires, we have to log timber or the forests become overgrown tinderboxes. Searching for the optimal balance between a thriving civilization and healthy ecosystems requires accepting limits in both directions.

With this in mind, there’s an irony in the environmentalist-inspired regulations that require water, stored in reservoirs behind artificial dams, to be released downstream in order to maintain year-round flows in rivers that used to run dry in dry years.

The solution to meeting the water requirements of farms, cities and ecosystems is to build more water supply infrastructure, not fallow millions of acres of prime farmland during a world food crisis. Capturing storm runoff through a combination of more off-stream storage and aquifer recharge can increase available water to farms and cities. 

With wastewater recycling, less water has to be imported to cities, and in the San Francisco Bay region, less water would have to flow through the Delta to flush out the nitrogen currently being discharged. Desalination can also deliver a drought-proof supply of new water.

Investing in water supply infrastructure creates options for Californians that do not require undermining an industry that helps feed the world. Build the solar farms in the hot Mojave, and save the valley farms.