SAN DIEGO -- The city will hold the first of three public workshops Monday to discuss potential water rationing in San Diego due to the ongoing drought and projected cuts to water deliveries.

The Metropolitan Water District of Southern California, which supplies most of San Diego's water, may soon slash deliveries to the region by as much as 20 percent, according to the mayor's office.

Mayor Jerry Sanders has warned that if the cuts run as deep as the city anticipates, San Diego would begin implementing a water allocation strategy for customers as early as July 1.

Penalties would be imposed on customers who exceed their allocations, according to Sanders' office.

The mayor has scheduled three public workshops to discuss how to implement water rationing fairly.

Monday's meeting starts at 6 p.m. Otay Mesa-Nestor Branch Library.

The need to cut back on water use in the city is necessitated by ongoing drought conditions and a judge's ruling that limits the amount of water that can be pumped from the Sacramento-San Joaquin River Delta in order to protect an endangered species of fish.

San Diegans have only cut back on their water use by about 5 percent since Sanders first raised the alarm by declaring a "Stage 1" water shortage emergency nearly a year ago.