Last week's flooding at the Lake Superior Zoo in Duluth, Minn., caused as much as $175,000 in damage to pumps and other electrical equipment in the lower level of the polar exhibit, zoo officials say, according to the Duluth News-Tribune. A culvert that was under repair got blocked under a BNSF bridge downstream from the zoo, and water backed up Kingsbury Creek during a heavy rain Aug. 18.

"The water just kept getting deeper and deeper and creeping up the hillside and moving back up to the polar shores exhibit," said Sam Maida, chief executive officer of Lake Superior Zoo. Finally reaching the exhibit's pumping system, grimy floodwater quickly rose about four feet in the polar shores basement.

"If the water had gotten any higher, we might have had an issue with what are we going to do with the polar animals," Maida said. "You can't just move a polar bear on a spur of the moment like that."

The flooded Kingsbury Creek has since receded and, after heavy sterilization, the zoo is back open for business. Some damage, however, cannot be undone, Maida said.

"Floodwaters got up into the polar building and down into the lower units where the pumps and the pump motors are and all the electronic gear that controls those," Maida said.

Although the six motors are running smoothly, zoo administrators say they fear wear and corrosion will make them unreliable. City officials say new pumps cost $25,000 apiece. The city is weighing its options.

"[The motors] do have a shortened lifespan, it's my understanding, and we will be dealing with the BNSF folks relative to that," city architect Terry Groshong said. The projected amount needed to bring polar shores back online: up to $175,000. Because BNSF's culvert caused the flooding, city and zoo officials expect that the railroad should pay 100 percent of the damage, Groshong said.

Maida agrees.

"Electronic components, those motors and such, that's a big investment, huge investment for the city and for the taxpayers," Maida said.

City officials say Duluth would front the money for repairs and be reimbursed later by BNSF.

The city owns the zoo and provides money for its operation. The zoo is managed by the Lake Superior Zoological Society, a nonprofit organization that exists solely to manage the zoo and its concessions.