Experts said it involves two water storage and delivery systems -- the federally managed Central Valley Project (or CVP) and the state-controlled State Water Project (or SWP), from which Kern County gets most of its water.

It's unclear exactly what, if anything, was "turned on" in California, but the Department of Water Resources said no military entered the state.

President Donald Trump claimed that the military entered California and turned on the water, but state water officials say the president's claim is false.