Water Disinfectant Agent: Chloramines

Lagoon Water

In February of 2004, in an effort to meet future water regulations and to better serve customers, the San Francisco Public Utilities Commission (SFPUC) converted the water disinfectant agent from Chlorine to Chloramines disinfection for its drinking water. Chloramines is a combination of chlorine and ammonia that offers a number of health benefits. It lasts longer in the water to more effectively remove pathogens, produces lower levels of disinfection byproducts, and may improve taste and odor. These benefits will provide San Francisco retail customers and its wholesale water customers, including the City of Foster City/Estero Municipal Improvement District (EMID), with increased protection from bacterial and viral contamination.

Sensitive Users

Chloraminated water is safe for people and animals to drink, cook with, bathe in, and for all other general uses. The change to chloramines will have long-term health benefits as it reduces the levels of disinfectant byproducts in drinking water. As with chlorine, sensitive users, such as kidney dialysis patients, fish and amphibian owners, and industrial/biotechnology businesses must take precautions prior to using the water. Chloramines, a combination of chlorine and ammonia, must be neutralized or removed for these purposes. Sensitive users can find out more information from the following resources:

  • Businesses seeking additional information, please contact your equipment supplier or current water treatment professional.
  • Fish, amphibian, and reptile owners, please visit the following websites:
  • Dialysis patients, please contact your dialysis provider or the National Kidney Foundation.
  • Some consumers may wish to reduce chloramines disinfection levels in drinking water at home.
    • The National Sanitation Foundation (NSF) website contains databases which can provide you with information about certified products that will reduce chloramines levels in your drinking water.
      www.nsf.org
      NSF Consumer Affairs: (800) 673-8010

Replacing Rubber Plumbing Parts

While safe for people and animals to drink, chloraminated water may degrade rubber components more quickly than chlorinated tap water. On rare occasions, you may experience small black flakes in your water and plumbing fixtures. These signs of degradation can be easily resolved by upgrading to high quality rubber (synthetic polymers such as neoprene) parts or flexible copper tubing. Tubing made of corrugated stainless flex or newer neoprene braided stainless steel will also work. Ask store personnel for assistance in selecting chloramine-resistant products when replacing rubber plumbing and irrigation components such as water supply hoses, toilet flapper valves, water heater flexible connection hoses, and sprinkler parts.

Chloramines Widely Used in the Bay Area and the United States

More than one-third of the country's water agencies have already switched to chloramines from chlorine as a final disinfection agent. In the Bay Area, these agencies include the East Bay Municipal Utility District, Santa Clara Valley Water District, Contra Costa Water District, Alameda County Water District, and the Marin Municipal Water District. Chloramines have been used nationally since 1917. In addition, based on a series of planning studies, converting to chloramines will allow the San Francisco Public Utilities Commission (SFPUC) to provide water that meets the stringent drinking water standards for disinfection byproducts, specifically the federal and state Disinfectant/Disinfection Byproducts Rule (D/DBP Rule).

Construction of Facilities

The system-wide chloramines conversion project will require construction of three (3) new facilities and the modification of existing facilities and operations at various locations along the SFPUC water supply system. New chemical feed facilities are being built in the Sunol Valley and at the Harry Tracy Water Treatment Plant in San Bruno. A 10,000 square foot dechloramination facility and a 2,000-foot long, underground contactor pipeline are being built at the Pulgas Water Temple site near Woodside. These changes will precede conversion of the water supply. Full implementation is scheduled for November 2003.

San Francisco Public Utilities Commission

The San Francisco Public Utilities Commission (SFPUC) is a department of the City and County of San Francisco that provides water, wastewater, and municipal power services to San Francisco. Under contractual agreement with 28 wholesale water agencies, the SFPUC also supplies water to 1.6 million additional customers within three (3) Bay Area counties. The SFPUC system provides four (4) distinct services: Regional Water, Local Water, Wastewater (collection, treatment, and disposal), and Power.

Phone: (415) 554-3155

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