(AP) - Water problems in Minnesota last year included industrial contamination in Bayport, fecal coliform bacteria in St. Augusta, and high arsenic levels in 18 communities including Blaine and Warroad, the state Health Department said Tuesday.
An annual survey of drinking water reported test results for 726 municipal systems and 237 non-municipal systems that supply subdivisions, prisons, hospitals and other places people live.
Health Commissioner Dianne Mandernach said the overall quality of Minnesota's public water supplies is good.
"When a problem is detected, the Health Department works with the water system to make sure corrective actions are taken," she said in a news release. "These actions always include notification of the residents affected by the problem."
Bayport is building a new water treatment plant. Officials in St. Augusta and Holloway told residents to boil water while they disinfected systems after finding fecal bacteria.
Officials in St. Cloud also told residents to boil water after finding E. coli contamination -- but that order was lifted after 20 additional tests showed no contamination. City officials said errors in collecting or handling samples might have led to an initial false test results.
The report also touched on testing for perfluorochemicals once manufactured by 3M Co. and now found in the water in several eastern Twin Cities suburbs. Health officials are studying the chemicals to determine what level of exposure is safe.
Other findings:
-Two systems had elevated levels of nitrates, which can harm infants.
-Fourteen systems had high readings for one or more radioactive elements.
-A tougher standard for arsenic, found naturally in the environment, took effect last year and more than 20 systems cut their levels to meet the new rule.
-Minnesota led the nation in high levels of copper in the water, with 28 systems above the recommended levels. The report said the groundwater in the state tends to absorb copper, a process that's accelerated by treatment to remove iron.
(Copyright 2007 by The Associated Press. All Rights Reserved.)