Nearly ten percent of Norway's 1234 waterworks facilities -representing 200,000 customers - failed to pass the E. coli test in the sampling taken by the Waterworks Register.
"It can have been a health hazard to drink water from these facilities," Truls Krogh, section director for water hygiene at Norwegian Institute of Public Health (NIPH), told Aftenposten.no.
Campylobacteriosis and norovirus are two typical illnesses caused by the presence of E. coli in drinking water, both result in vomiting and diarrhea. Campylobacteriosis is transmitted via animal excrement, norovirus via human excrement.
In 2005, 2,631 persons contracted campylobacteriosis in Norway, 443 in Hordaland where fully 21 waterworks failed the E. coli test.
In addition, 1,300 Bergen residents became ill after drinking water containing the Giardia bacteria, attributed to sewage emission into the water supply.
Many of the waterworks with positive E. coli results are small facilities with limited resources.
"The water is dirty because the waterworks have poor controls of procedure. Many do not have purification and those that do, do not have proper control of purification," Krogh said.
Brynjulf Melhuus, division head for water, feed and by-products at the Norwegian Food Safety Authority, said that work is underway for a campaign to increase FSA waterworks supervision at district offices.
"Supervision of waterworks may have been a downgraded activity at certain district offices. By increasing supervisory activities it will be easier to implement measures to improve water quality," Melhuus said.
