Lower groundwater levels can prevent drainage of water and salts from a basin and increase aquifer salinity that eventually renders the groundwater unsuitable for use as drinking water or irrigation without expensive desalination. Pauloo et al. (2021) demonstrate this process for the Tulare Lake Basin (TLB) of California’s Central Valley. Even if groundwater pumping does not cause overdraft, it can cause hydrologic basin closure leading to progressive salinization that will not cease until the basin is opened by allowing natural or engineered exits for groundwater and dissolved salt. The process, “Anthropogenic Basin Closure and Groundwater Salinization (ABCSAL)”, is driven by human water management.