The crux of this transport system is the Sacramento-San Joaquin Delta, a sensitive marshland region where two of the state’s largest rivers converge and flow out into the San Francisco Bay. This area is also the point where endangered fish species like Chinook salmon enter from the Pacific and swim upstream to spawn.

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.

The U.S. Army Corps of Engineers has released water from two reservoirs in the foothills of the southern Sierra Nevada to meet President Donald Trump’s recent directive to funnel more water to Southern California, but some officials there question whether it will actually prove helpful.