Fish lost to chloramine Fish lost to chloramine (July 09, 2004)

Chemical disinfectant has a downside

By Jon Wiener

Fish in ponds and tanks throughout the city have died from exposure to a new chemical in the water, but city officials believe they have averted other, more disastrous side effects.

The chemical additive, chloramine, is used as a disinfectant in water supplies throughout the nation. According to water experts, it is safe to drink, but if not treated, it can kill not only fish, but also kidney dialysis patients. Chloramine can eat through the lead in pipes and the rubber in plumbing fixtures. And there is growing evidence that chemically sensitive users can have serious allergic responses (see sidebar on P.9).

The San Francisco Public Utilities Commission supplies drinking water from the Hetch Hetchy reservoir to approximately 90 percent of Mountain View. (The Santa Clara Valley Water District, which has long used chloramine, provides the rest.) In February, it followed the lead of other water suppliers in the Bay Area and stopped using chlorine as a disinfectant after indications that it was bonding with organic compounds and forming low levels of carcinogens.

Chloramine does not break down nearly as quickly as chlorine, preventing this problem but creating a new one. Chlorinated tap water can be left exposed for a day or so before the chlorine dissipates entirely. Fish owners who have tried that since February have been in for a rude surprise.

Pet poison

"Two or three times a week, people come in with tears in their eyes," said Patrick Andorfer, whose girlfriend Chloe Mezilis owns Seascapes on Castro Street. Andorfer, a diabetic, said he believes that the rashes on his arms and his recent hospital trips have been due to exposure to chloramine.

Next door to Seascapes, the Food Street restaurant lost an entire display of 10 three- to four-year-old koi, a colorful and expensive Japanese carp. Owner Alvin Au said he had received information from the city about chloramine but did not read it.

Chloramine kills fish within 10 minutes of exposure because it enters their bloodstream directly via their gills, rather than going through the digestive process it does for other animals. Especially susceptible are owners of ponds with automatic water fillers, who are less likely to be aware of the chemistry in their ponds.

"When it comes to ponds, people are relying on the mechanics more," said Matt Hogrefe, owner of Aquatic Variations on Grant Road. "They're not thinking they're pumping poison into the water. Customers go on vacation and lose their entire ponds."

Both Seascapes and Aquatic Variations sell four-ounce bottles of water conditioner to treat water in smaller tanks. Garbage cans rigged with hoses and conditioner treat the hundreds of gallons of water used weekly in the stores. Large pond owners may need to buy carbon filters from Internet retailers.

Preventing more deadly impacts

The city conducted an extensive public information campaign before the conversion in February, sending out fliers and brochures to households and businesses in three different languages. While not every fish owner read and followed the city's directions, two of the more serious threats posed by chloramines, to dialysis patients and lead pipes, have failed to materialize.

Geography and history play a part here. El Camino Hospital, with its 175-patient dialysis center, is located in the area of town that gets its water from the Santa Clara Valley Water District (SCVWD), which has been using chloramine for over a decade. The machines at El Camino treat the water before using it in the dialysis process.

There is a negligible amount of lead in the pipes in Mountain View, unlike in the older city of Washington, D.C., where the chloramine-lead link has been documented. According to utilities services manager Dave Serge, the city has been monitoring lead levels in the area supplied by SCVWD since it first included chloramine in the early 1990s.

"We've actually seen a decrease in lead and copper levels in that time period," said Serge. "We're not overly concerned with San Francisco water having the chloramines."

E-mail Jon Wiener at jwiener@mv-voice.com

E-mail a friend a link to this story.