Brainerd will add chlorine to its water distribution system after total coliform bacteria was found in water samples near a construction site in the city.
Brainerd Public Utilities Superintendent Tom Phelps said the coliform bacteria were found Friday near the South Eighth Street construction and utility employees flushed the water system all weekend. Chlorine will be added to the city's water supply on Tuesday to disinfect the system.
Phelps said people should not be alarmed by the presence of total coliform bacteria in the drinking water.
Background/overview: Biological organisms are among the oldest health threats to drinking water quality and the agents currently responsible for most waterborne diseases. They are the most common contamination incident water operators will encounter. Potential sources of contamination include sewers, septic systems, feedlots and animal yards.
Role of coliforms in detecting contamination: Unfortunately, specific disease-producing organisms present in water are not easily identified. It would be very difficult, expensive and time-consuming to monitor for them. For this reason, it is necessary to select an easily measured indicator organism whose presence indicates that pathogenic organisms may be present. A group of closely related bacteria, the total coliform, has been selected as an indicator of harmful organisms in drinking water.
Sources of coliform bacteria: Total coliform bacteria are common in the environment, such as in soil, and the intestines of animals and are generally not harmful. Fecal coliform and Escherichia coli, or E. coli, bacteria are found in greater quantities than total coliform in animal fecal matter. If fecal coliform or E. coli is detected along with total coliform in drinking water, there is strong evidence that sewage is present; therefore, a greater potential for pathogenic organisms exists.
Response to coliform detection: The Minnesota Department of Health monitors drinking water for public water supplies on a routine basis. If only total coliform is detected without the presence of fecal coliform or E. coli, the source is most likely from contamination from the environment, introduced during construction or while repairs to plumbing or a water main were under way. The system will identify the source of the contamination, correct the problem and thoroughly disinfect its system. The public will be notified of the situation; however, unless unusual circumstances exist to cause particular concern about the safety of the water, a boil order will not be issued.
Health effects: Symptoms of waterborne diseases may include gastrointestinal illnesses such as severe diarrhea, nausea, and possibly jaundice as well as associated headaches and fatigue. Not all people will be affected to the same degree; young children and the elderly are usually more susceptible.
Source: Minnesota Department of Health
"There's no concern," Phelps said. "It's not an emergency."
If only total coliform is detected without the presence of the more harmful fecal coliform or E. coli, as is the case in Brainerd, the source is most likely from contamination from the environment, introduced during construction or while repairs to plumbing or a water main were under way, the Minnesota Department of Health reported.
Phelps said the source of the coliform bacteria has not been found. The utility will continue to search for the source as it disinfects the city's water system with chlorine.
The Minnesota Department of Health was notified of the coliform detection and officials will meet with the Brainerd Public Utilities Commission at 9 a.m. Tuesday to discuss the situation.
Total coliform bacteria are generally not harmful themselves, Brainerd Public Utilities said in a news release Monday. Coliforms are bacteria which are naturally present in the environment and are used as an indicator that other potentially harmful bacteria may be present. Coliforms were found in more samples than allowed and this was a warning of potential problems in Brainerd's system, the utility reported.
Dave Schultz, Minnesota Department of Health regional supervisor in St. Cloud, said in most cases where total coliform bacteria is detected in drinking water there is no disease-causing bacteria.
Schultz said the Department of Health is not recommending people boil their water. However, as a precautionary measure, people with infants, the elderly, people with compromised immune systems and people with other health problems should seek alternative sources of water, either from filtered and tested water available at the Water Treatment Plant unfluoridated tap or with bottled water. Guidelines on ways to lessen the risk of infection by microbes are available from the Safe Drinking Water Hotline at (800) 426-4791. Chemicals also are available commercially to neutralize the chlorine that will be added to the water.
"In many cases we just don't see any illness at all," Schultz said.
At 3 p.m. Tuesday Brainerd Public Utilities will be adding chlorine to the system until further notice. Phelps said the system will be flushed and tested. How long the utility will be putting chlorine into the city's water supply will depend on how long it takes for the chlorine to get through the city's delivery system, he said.
Schultz said the Minnesota Department of Health always recommends permanent chlorination of municipal water systems, but Brainerd chooses not to do so.
"If it did, this problem probably would not occur," he said.
Brainerd will be adding chlorine at a ratio of two parts per million, which is at levels found in water delivery systems that are permanently chlorinated.
"It will be within normal drinking water levels," he said.
The addition of chlorine to disinfect the water may react with iron or manganese that may be deposited in water mains, breaking it loose and causing some temporary discoloration, black or reddish brown, of the water. It does not pose a health threat, Brainerd Public Utilities said in a news release.
Residents can let the water run for a few minutes to flush the faucets of the discolored water before using it for cooking or laundry. The chlorine in the water may cause some problems in fish tanks as well as in commercial operations like bait shops.
Total coliform bacteria was found in Pine River's water system in 2005. The system was disinfected, tested and there were no reports of illness.
MATT ERICKSON may be reached at firstname.lastname@example.org or 855-5857.
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