Officials are advising people to stay out of the water at three Duluth beaches where elevated E. coli bacteria levels were found.
The Minnesota Pollution Control Agency issued the advisories Friday for Leif Erikson Park Beach, Park Point New Duluth Boat Club and Hearding Island Canal Beach.
Testing on Wednesday indicated elevated E. coli levels, which might be caused by fecal contamination. The beaches were to be tested again Friday.
The Minnesota Pollution Control Agency oversees beach testing on Lake Superior, but testing on 40 beaches didn't start until late this summer as the agency worked out an agreement with a contractor hired to do the testing.
Beaches in Wayzata, Bemidji and Minneapolis have all been closed this summer because of high bacteria levels. Swimmers who ingest water contaminated with E. coli can get sick, so many -- but not all -- beaches in Minnesota are tested regularly during the summer months.
The beaches in Duluth are not closed, but the MPCA urged swimmers to heed the advisory.