As California faces the prospect of a fourth consecutive dry year, officials with the Metropolitan Water District of Southern California have declared a regional drought emergency and called on water agencies to immediately reduce their use of all imported supplies.

The decision from the MWD’s board came about eight months after officials declared a similar emergency for 7 million people who are dependent on supplies from the State Water Project, a vast network of reservoirs, canals and dams that convey water from Northern California. Residents reliant on California’s other major supply — the Colorado River — had not been included in that emergency declaration.

“Conditions on the Colorado River are growing increasingly dire,” MWD Chairwoman Gloria Gray said in a statement. “We simply cannot continue turning to that source to make up the difference in our limited state supplies. In addition, three years of California drought are drawing down our local storage.”

Officials said the call […]