Utility-scale solar farms bloom in California desert

Sunny Palm Springs, California is one of the densest areas of solar development in North America. But the future ability to meet the state’s and nation’s ambitious renewable energy goals depends on a very limited water supply. Operating solar farms doesn’t require much water, but environmental law requires developers to mitigate dust during construction. “Importing” water from elsewhere is too costly, so developers rely on groundwater during construction.

The same area wells that supply the only fresh water source for Desert Center residents are being depleted as solar projects are being built on public land, overseen by the U.S. Department of Interior’s Bureau of Land Management (BLM).

“The federal agency knew the construction of the solar projects could impact local wells and may even be over-drafting the aquifer beneath them, according to former BLM staff, studies on the basin and public documents from the agency’s environmental assessments of the projects,” writes journalist Wyatt Myskow.

If groundwater use by solar companies dries up local wells, the BLM requires developers to “reduce pumping until the aquifer returns to levels that allow wells to resume operations and cover the expenses for replacing equipment and wells.” Local groundwater well owners report receiving no help so far.

The BLM’s 2012 Western Solar Plan divided and labeled 298,321 acres of public lands as “solar energy zones,” areas perfect for developing the renewable energy. Nearly half of the zones are in the same zone as Desert Center. The clean energy economy  acceleration plan is now being reviewed by the BLM.

So far around 20,000 acres of land has been developed in the solar energy zone. Another 120,000 acres are available for solar development. And development is unlikely to end anytime soon. The potential to open up areas for solar development in five more states and across even more public land in states that are already being developed, the agency told Inside Climate News.

Limited data exists about the Chuckwalla Valley Groundwater Basin, but studies suggest significant overdraft compared to the rate of aquifer recharge.

The BLM reported that there was enough groundwater for the most recently approved projects from Intersect Power and Clearway Energy Group in its environmental assessments of the proposed developments, but also found data was limited and the basin could already be overdrawn. Even if it wasn’t being overused, the project “may adversely affect operation of nearby wells,” the assessment stated, Myskow reports.

A different solar project also proposed by Intersect Power would require another 1,000 acre-feet of water during two years of construction, and a third development proposal would need water but the amount has not been determined.

The water assessments for each recently approved project found the recharge of the aquifer from rain could range from 206 to just over 20,000 acre-feet a year.

Under California’s Sustainable Groundwater Management Act (SGMA), passed in 2014, groundwater sustainability agencies (GSAs) have formed to regulate and restrict groundwater use to avoid long-term issues in high-priority overdrafted basins.

But the Chuckwalla Valley Groundwater Basin is designated as a low-priority basin, so efforts to more accurately measure and avoid excessive extraction haven’t been made.

Furthermore, the state law doesn’t apply to federal lands, which is where most of the utility-scale solar projects are being built.

Myskow reports that the BLM has not answer questions about groundwater overdraft mitigation measures, if it is investigating wells going dry, if it has been monitoring the Chuckwalla basin, or work with local communities. 

But in its environmental assessment for recently approved solar projects, the BLM found water used by solar project development could affect local wells. Under baseline conditions, it found the basin would have a surplus of 2,390 acre-feet. But the lack of data on the basin makes “performing a detailed analysis” challenging. The water supply assessment found the aquifer could already be overdrawn by 6,685 acre-feet of water under lower precipitation and water inflow conditions.

Kisters supports sustainable groundwater data management with water level and water quality sensors and data systems as well as optimal renewable energy generation by supply weather sensors and forecast data to lessen attenuation. We want to empower your decisions of tomorrow with water, weather, environmental and renewable energy data of the highest quality.