SAN FRANCISCO (KCBS)—San Franciscans are being asked to participate in a nationwide water conservation challenge, but at the same time, the public is being urged to drink its fill of water from the Hetch Hetchy system.

Mayor Ed Lee is asking merchants and residents to sign up on line at for the National Mayor’s Challenge for Water Conservation. It’s a month-long contest that will pick the city that does the best job of turning off the tap.

The water that flows from Hetchy Hetchy is one of the city’s most precious commodities, but Mayor Lee said if we don’t conserve it, it won’t continue to fill reservoirs like it has been, which would lead to problems.

Last year’s heavy rains have left the water supply in good shape with enough in the system for 2.5 million customers.

Public Utilities Commission General Manager Ed Harrington said even without a competition San Franciscans only use 80 gallons per person a day, which is half the state average.

“San Franciscans already do a great job, but it reminds you how long of a shower do you take? What about a low-flush toilet?” Harrington rhetorically asked.

At the same time both the Mayor and the PUC Chief are urging San Franciscans to drink the high quality Hetch Hetchy water than comes out of the tap and not waste their money on bottled water that comes in single use plastic containers that pollute the environment.

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