Marin County water officials are thinking of buying three desalination plants to bolster local supplies, but they’re facing an unlikely competitor — Saudi Arabia’s Crown Prince Mohammed bin Salman.

The Marin Municipal Water District, which might deplete its reservoirs by next summer if the drought continues, had considered renting two portable desalination plants for nearly $30 million from Osmoflo, an Australian company. Last week, the district staff said a third plant has become available and that purchasing them might be less expensive than renting.