Excelsior's public beaches were closed Tuesday after tests showed levels of E. coli above the recommended standard.

The city's beach on Lake Minnetonka was closed for a day last week due to high E. coli levels, and Wayzata's public beach had been closed the week before for two days before being reopened.

Excelsior officials said the beaches will reopen when E. coli levels fall.

It's not uncommon for Minnesota beaches to be closed due to E. coli contamination in the summer, since it can be produced by waste from geese, ducks and other wild animals as well as boaters dumping waste overboard.

The bacteria can sicken swimmers, causing diarrhea, abdominal cramps and occasionally more serious problems.

For more information, call Excelsior City Hall at 952-474-5233.