About 1,000 East Honolulu residences receive their drinking water from Aina Koa Water Well II, where broken chlorination equipment led to trace amounts of E. coli bacteria found in water samples taken in the area last week, Honolulu Board of Water Supply officials said Monday.
The problem was fixed and water in the area determined safe to drink by Friday, within 24 hours from the time the first microbiological sampling, taken near Aina Koa Neighborhood Park, confirmed low chlorination levels and the possibility of E. coli. The sample was taken Wednesday but completed Thursday, as testing for E. coli takes 24 hours to complete.
The state Department of Health, after being told by water officials of their findings, on Friday night issued the water agency a notice of violation.
The public was notified through the media Saturday.
"This is the first time we’ve ever received this type of notice," agency spokeswoman Tracy Burgo said.
Exposure appears to have been minimal.
Board officials traced the low levels of chlorination to the Aina Koa Well II, where they discovered the malfunctioning chlorinator. Chlorinators are used to inject chlorine into the water to disinfect it of E. coli and other bacteria.
Board officials don’t know for sure when the malfunction occurred before it was detected, but "based on our samples collected this week, we estimate about 24 hours," Burgo said.
The well is tested monthly, she said.
A repeat sample taken Thursday confirmed a final result of E. coli positive, while all other samples from the area were E. coli negative, Burgo said.
Ann Zane, supervisor of the compliance section of the state Health Department’s Safe Drinking Water Branch, said only one of three samples taken from the vicinity of the park tested positive for E. coli on Thursday, suggesting the presence of the bacteria was not widespread in the area or existed for long.
Subsequent tests have come up negative.
E. coli, found in human and animal waste or in tropical, subtropical or temperate soils, can cause diarrhea, cramps, nausea, headaches or other ailments in humans. E. coli in water can be destroyed either through boiling or chlorination.
For more information, visit the board’s website at bit.ly/1caSA5L.