Quality control of Hetch Hetchy water

(KTSF by Jessie Liang)

Water is the critical resource for the survival of all things and human activities. So how is the quality of the Hetch Hetchy water that provides to 2.5 million people in the Bay Area?

“I like the water. Tastes good.“

“Very good. I like San Francisco water.”

“The water is very good. I’m not afraid of it. I don’t use any purification or anything like that.”

“Every time I wash my hands, I can feel that the water is so smooth.“


Federal EPA Regional Director Jared Blumenfeld said, “The water that comes out of Hetch Hetchy and its pipes to San Francisco and many residents in the Bay Area is some of the cleanest drinking water in the world.”

The federal EPA, which oversees a national water quality standard, declares that the Hetch Hetchy water is exempt from filtration processes mandated by the Safe Drinking Water Act.

Ed Harrington, General Manager of the San Francisco Public Utilities Commission, said, “We filter local water but 85% of the water that comes out of Hetch Hetchy does not need to be filtered.”

Water Operation Analyst Adam B. Mazurkiewicz said, “To avoid body contact, you’re not allowed to swim in the reservoir or swim in any of the tributaries within a mile of the reservoir.”

SFPUC spokesman Tyrone Jue said, “We allocate about $5 million a year to the National Park to maintain the trails and also the water quality of the reservoir.”

However, the water has to go through disinfection before it’s ready for public consumption. Superintendent of the Sunol Water Filtration Plant of SFPUC Gary K. Williams said, “We have chlorine, which is the primary disinfectant. We add fluoride, which is good for the teeth. It also creates acid that would reduce ph in the water. We also add CO2 and mix it with the water to make carbonic acid that also lowers the ph in the water.”

In April 2012, the federal EPA requires that all water utilities that deal with non-filtration drinking water goes through a second disinfection. For that purpose the Tesla Water Treatment Plant in Tracy uses an ultraviolet light (to sterilize water).

“We inactivate the cryptosporidium. That’s the bug we’re trying to target with UV.”

The Tesla plant is the largest UV plant in California, treating 215 million gallons of water a day, while the Sunol and Harry Tracy treatment plants are responsible for its water in the Bay Area reservoirs.

SFPUC spokeswoman Alison A. Kastama said the Harry Tracy Plant “basically filters the disinfectants that come out of those reservoirs for use in this drinking water system.” In January last year, some customers in San Francisco and the Peninsula complained about a foul odor in the water. The SFPUC said its treatment plants could remove algae particles but algae produce compounds that could create odor in drinking water temporarily. However, the water remained safe to drink.

Health experts said Hetch Hetchy water contains a lot of healthy natural minerals. June M. Weintraub of  the  Department of Public Health said, “We have calcium, magnesium, potassium. These are the materials that bottled water manufacturers want to add to their water on purpose to make it taste better. But here in San Francisco we have great water that already tastes good and is safe.”

In complying with federal and state rules, the SFPUC conducts tens of thousands of tests a year and submit their findings to the federal, state and local authorities, making sure that there’s no potential source that will cause sickness or pollution. The agency wants to maintain a quality level that’s as good as or exceeds required standards.

If you have any concerns with water quality, call 311 or visit SFPUC website sfwater.org, Look up its water quality report or water conservation page.

(Copyright 2012 KTSF.  All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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