By David Bailey
(Reuters) - Heavy rains pounded northern Minnesota on Wednesday, forcing the evacuation of dozens of homes, causing mudslides and sinkholes, and swamping a zoo where several animals died and a polar bear briefly escaped its enclosure, officials said.
Officials said the flooding in the Duluth area, on the edge of Lake Superior, was the worst the city had seen in four decades.
"The last time there was something similar was in 1972," Duluth police spokesman Jim Hansen said in a telephone interview.
The sheets of rain turned some hillside roads into rivers, popped off manhole covers and flooded the Lake Superior Zoo, where several barnyard animals died, including a donkey, sheep and goats.
"It's pretty devastating," said Kara Gilbert, an office support specialist who was answering telephones at the zoo. "We can all look out and see half of the zoo under water."
The zoo's polar bear, Berlin, exited her exhibit and was tranquilized by the zoo's vet and quarantined, the zoo said. Two seals also escaped their enclosures: One was captured outside zoo grounds and the second was recovered on zoo property.
"A few of the animals got out of their enclosures, but they are contained and doing fine," Gilbert said.
A flash flood warning was in effect for Duluth and other parts of the area until 10:30 p.m. Five to nine inches of rain fell overnight and up to three more inches were expected, the National Weather Service said.
Flash flooding was possible from Grand Marais, in the far northeast corner of the state, southwest along the north shore of Lake Superior through Duluth.
Police helped residents leave 40 to 50 homes in Duluth's Fond du Lac neighborhood. About 18 miles southwest of Duluth, parts of the low-lying town of Thomson were also evacuated.
Hansen said it was unclear when people could return.
Numerous roads in Duluth and the surrounding area were under water, and parts of area highways and Interstate 35 in Duluth were impassable. Officials warned residents that the standing water was likely unsanitary.
Duluth Mayor Don Ness declared a state of emergency and the Red Cross opened emergency shelters in the area. Governor Mark Dayton declared a state of emergency in eight counties, which will allow the National Guard to be deployed if needed.
No deaths or injuries as a result of the heavy rains and flooding were reported.
The Jay Cooke, Savanna Portage and Moose Lake state parks were closed until further notice because of the flooding, the state natural resources department said.
About 350 Minnesota Power customers were without power on Wednesday because of flooding, and the company was passing the increased water flows on the St. Louis River through its dams, a process that can take several days, officials said.
"Our gates are wide open and passing the maximum amount of water they can," said Bonnie Carlson, Minnesota Power's hydro operations manager, who said there was no threat to the dams.
(Reporting by David Bailey; Editing by Cynthia Johnston and Jackie Frank)