California overdue for major earthquake that could cripple water supply system, new study says

Three fault segments running beneath Northern California and its roughly 15 million people are overdue for a major earthquake, including one that lies northeast of San Francisco and near the dams and canals that supply much of the state’s water, according to a geological study published Monday.

The three segments and one other in Northern California are loaded with enough tension to produce quakes of magnitude 6.8 or greater, according to a geological study published Monday, according to a geological study published Monday.