June 20 (Reuters) - Heavy flooding pounded the Duluth, Minnesota, area on Wednesday forcing the evacuation of dozens of homes, causing mudslides and sinkholes that trapped cars, and flooding the Lake Superior Zoo where a polar bear and two seals escaped their enclosures, officials said.
No deaths or injuries had been reported from the flooding that officials said was the worst Duluth had seen in four decades. Officials warned residents that conditions could change rapidly.
"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 man hole covers and flooded the Lake Superior Zoo, where several animals died. A polar bear and two seals also were among animals to escape their enclosures, but were recovered.
"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."
A flash flood warning was in effect for Duluth, a Lake Superior port city, and other parts of the area until 10:30 p.m. local time. Five to 9 inches of rain fell overnight and up to 3 more inches were expected, the National Weather Service said.
Flash flooding was possible from Grand Marais, Minnesota, 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, Minnesota, 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 Duluth area.
The Jay Cooke, Savanna Portage and Moose Lake state parks have been 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 Jackie Frank)