Activists and local government officials across Monterey County have banded together to fight a proposed desalination plant that could double the cost of water for some residents and endanger an aquifer that serves low-income communities.

Opponents say the plant could cause saltwater to seep into the Salinas Valley Groundwater Basin, the aquifer that provides freshwater to much of Monterey County.

California American Water (CalAm), an investor-owned public utility, however, says the plant is needed to fulfill the Monterey Peninsula’s water needs, and that the effects on other communities will be minimal, if any.