LOS ANGELES — Faced with a persistent drought and the threat of tighter water supplies, Los Angeles plans to begin using heavily cleansed sewage to increase drinking water supplies, joining a growing number of cities considering similar measures.
Mayor Antonio R. Villaraigosa, who opposed such a plan a decade ago over safety concerns, announced the proposal on Thursday as part of a package of initiatives to put the city, the nation’s second largest, on a stricter water budget. The other plans include increasing fines for watering lawns during restricted times, tapping into and cleaning more groundwater, and encouraging businesses and residents to use more efficient sprinklers and plumbing fixtures.
The move comes as California braces for the possibility of the most severe water shortages in decades.
Snowfall in the Sierra Nevada, which supplies about a third of Los Angeles’s water, is short of expectations. At the same time, the Western drought has lowered supplies in reservoirs, while legal rulings to protect endangered species will curtail water deliveries from Northern California.
Worsening the problem, Los Angeles is expected to add 500,000 people by 2030, forcing the city to examine new ways to meet demand. One option off the table, Mr. Villaraigosa said, is a repeat of the city’s troubled history, fictionalized in the movie “Chinatown,” of diverting a distant river southward to slake the city’s thirst.
The city, pushed by legal claims, is already paying millions to restore dried-up portions of the river, the Owens.
“There simply are no more holes or straws to pitch,” Mr. Villaraigosa said at a news conference at a water plant.
Many cities and towns across the country, including Los Angeles, already recycle wastewater for industrial uses and landscaping.
But the idea of using recycled wastewater, after intense filtering and chemical treatment, to replenish aquifers and reservoirs has gotten more notice lately because of technological advances that, industry leaders say, can make the water purer than tap water.