Tampa needs to provide refuge for manatees

If Tampa officials want to move ahead with a $5.7 million project to improve the ecology of the lower Hillsborough River, they're going to have to keep the manatees toasty warm.

That's the crux of an agreement between federal and state wildlife officials, who have come up with a proposed solution to restart the stalled project - balancing the city's obligation to protect the lower river's delicate ecosystem with a federal mandate to protect the endangered species.

The deal between the state, county and the federal government deals with a litany of complicated issues that also involve the city and the regional water district. The issues encompass everything from having enough water to supply a thirsty city to keeping salt water out of the river to, and this was the sticking point, protecting the herds of sea cows that seek out the relatively warm waters of Sulphur Springs each winter.

The solution? A thermometer.

After a year of wrangling over details, the city and regulators have reached a tentative agreement that will allow the project to move forward. The city will be required to monitor river temperatures near the spring to ensure it stays around 68 degrees. If it drops below that, even for a short time, the city will be required to release additional spring water to raise the temperature.

"When temperatures in the Gulf of Mexico drop in the winter, these are the kinds of areas manatees go," said Anne Richards, an environmental specialist with the Florida Fish and Wildlife Conservation Commission. "It provides a vital warm-water refuge."

For decades, the city has pumped water from Sulphur Springs to the Rowlett Park dam to supplement millions of gallons a day it draws from the river for drinking water supplies. The reduced flow of fresh water has upset the river's chemistry, studies have indicated.

To improve the river's health, the city and Southwest Florida Water Management District agreed in late-2007 to split the cost of $40 million in projects to increase river levels. The Sulphur Springs project required the city to modify pumps and barriers, or weirs, used to keep brackish tidal water out of the spring when water is being pumped up to the dam.

But regulators put the brakes on the Sulphur Springs project last year, citing concerns that it might imperil manatee herds that congregate near the underground artesian.

Steve Daignault, who oversees the Sulphur Springs project as Tampa's public works and utilities administrator, said that should satisfy federal requirements to protect the manatee while allowing the city to meet its minimum flow needs on the lower river.

"As soon as we get the permits, we are ready to move ahead," he said.

Under the agreement, the U.S. Geological Survey will install and maintain a temperature gauging station on the river. The data will be collected and transmitted every 15 minutes.

Scientists say manatees, which are protected under the Endangered Species Act, can die of starvation if their body temperature drops too low. FWC regulators cite records back to 1974 showing 9 manatees within a one-mile radius of the spring have died.

Sulphur Springs and other natural thermal outfalls will become increasingly important for manatees in the future, as man-made warm-water refuges such as the one near Tampa Electric Co.'s Apollo Beach power plant are eliminated, according to wildlife regulators.

Likewise, bodies of water like the lower Hillsborough need continuous fresh water flow to provide crucial habitat for fish, shellfish and aquatic birds. As Tampa has grown, the city has taken more water from the river above the dam to boost drinking water supplies.

In 1999, Swiftmud set a minimum flow at the Rowlett Park dam of 10 cubic feet a second, or about 6.5 million gallons a day. The decision angered environmental groups that charged that the decision was based on backroom politics, not scientific studies.

A group of homeowners calling themselves Friends of the River hired a lawyer and filed a challenge in state court seeking to increase the district's minimum flow standards.

Before the challenge could be heard, however, city officials and the water district agreed that the new minimum flow should be 24 cubic feet a second during the dry season, from April to June, and 20 the rest of the year.