TAMPA City officials said a rodent chewed through an underground power line this afternoon to knock out electricity at Tampa's water treatment plant for half an hour, forcing a boil water notice for all the 500,000 people who use the system.

The notice is precautionary and not mandatory, county health officials said, because there was no break in the city water lines. People most at risk include infants, those with open wounds and anyone who recently underwent surgery.

City officials said at an afternoon press conference that the city of Tampa water system serves half a million people during the day, in the city and just beyond. The number will drop about 100,000 when some workers leave the city this afternoon and return home.

The outage occurred about 1:30 a.m. at the David L. Tippin Water Treatment Facility along the Hillsborough River when one of two supply lines to the plant was cut. Inside the plant, a switch should have flipped to prevent an outage but it failed, officials said.

Tampa gets its water from the river and is the largest community in Florida to draw its supply from surface water rather than underground supplies.

The system was down half an hour before a diesel generator kicked in. There was minimal loss of the pressure in the lines that keeps bacteria in untreated water from entering, officials said.

Still, they issued the boil water notice as a precaution.

Restaurants are facing an especially precarious situation as they need to both cook and wash dishes. Many use water purification systems for flavor, but they are among some of the largest users of city-supplied water.

"We're not preparing any meals with any city water," said Casey Gonzmart, one of the family owners of the Columbia Restaurant in Ybor City. "We have a large enough surplus of clean dishes to serve several hundred meals."

Commercial dish washers heat water to especially high temperatures, but not to the boiling point.

As for how the restaurant will serve meals in the days ahead, he said, "We're all the same boat on this, and will have to take the proper precautions." If it came down to it, Gonzmart said they're willing to wash dishes in bottled water.

Grocery stores, meanwhile, started preparing for higher demand of bottled water. "Our distribution center is right nearby in Plant City," said Sweetbay Supermarket spokeswoman Nicole LeBeau. "So we can have bottled water easily restocked and bring in more."

Additional information and details will be provided as they become available.

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