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Manatee refuge puts river flow project on hold

Photo by KATHY MOORE

A project to increase the amount of freshwater flowing into the Hillsborough River is on hold over concerns by state regulators over a manatee habitat near Sulphur Springs Park.

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By CHRISTIAN M. WADE | The Tampa Tribune

Published: October 16, 2009

TAMPA - When temperatures in the Gulf of Mexico drop in winter, herds of manatee meander slowly up the Hillsborough River in search of warmer water.

One of the spots where they are known to congregate is Sulphur Springs Park, where temperate water from an underground artesian spring flows into the river.

Tampa also relies on the spring, but for a different reason. The city has, for decades, pumped water from the spring to the Rowlett Park dam to supplement the millions of gallons a day it takes from the river to provide drinking water for its huge population.

City officials want to increase the amount of water they pump from Sulphur Springs to comply with a mandate from the Southwest Florida Water Management District to replenish the lower Hillsborough with enough fresh water to improve the ecosystem.

But the city now finds itself caught between requirements to restore the health of the river and efforts to protect an endangered species.

State environmental regulators are concerned that the project – one of several intended to increase freshwater levels along the lower Hillsborough – could pose a threat to the manatees that flock to the thermal pool in winter by restricting their access to the area.

"Springs are vital habitats for manatees," said Kipp Frohlich, head of the Florida Fish and Wildlife Conservation Commission's imperiled species division. "We need to be sure this project won't drive them away before we can give them a blessing to move ahead."

City officials argue that the impact on the manatees from the project will be minimal.

They point to previous studies indicating the manatees rarely use the spring, preferring the larger and much warmer thermal refuges around Tampa Electric Co.'s Apollo Beach power plant.

"We are hoping that we'll be able to resolve this issue, so we can move ahead with the project," said Steve Daignault, the city's administrator for Public Works and Utilities.

To do that, the city needs a permit from the U.S. Army Corps of Engineers, which has put a review of the project on hold while the wildlife commission studies the issue.

"Because endangered species are involved, that issue has to be resolved before we can issue a permit," said Charles Schnepel, chief of the Corp's Tampa Regulatory Sector.

The delay in getting a permit has prompted Tampa officials to ask Swiftmud to extend the deadline for complying with the minimum flow requirements for another year.

Swiftmud is expected to vote on the city's extension request at its Oct. 29 meeting.

Experts say manatees, which are protected under the Endangered Species Act, can die of starvation if their body temperature drops too low during the cold winter months.

"They're a subtropical species that don't generate a lot of body heat," said Patrick Rose, executive director of Save the Manatees. "If they get too cold, they just stop foraging."

The Sulphur Springs project calls for modifying the series of barriers the city has to prevent brackish tidal water from entering the spring to compensate for increasing the amount of fresh water the city plans to pump back up river below the dam.

Manatees are known to swim between the gates of the barrier system to get to a thermal pool, and regulators are concerned that decreasing the gate opening will keep them out.

"If you restrict access to the spring, that's a big problem," said Mike Thompson, general manager of the Hillsborough County Environmental Protection Commission's wetlands and watershed management division, which is also reviewing the city's permit request.

The Hillsborough River has been dammed since the 1880s, and the city's reservoir has supplied drinking water since the early 1900s. Until the 1970s, water flowed through the dam almost every day. Since 1973, however, the number of no-flow days has increased to an annual average of 158 because of drier weather and much greater water usage.

The reduced flow of fresh water has upset the river's chemistry, studies have indicated.

The river is the main source of drinking water for more than 650,000 city residents, and Tampa officials say allowing more water to flow through the dam is not an option.

In 1999, Swiftmud set a minimum flow at the Hillsborough River dam of 10 cubic feet per second, or about 6.5 million gallons a day. The decision angered environmental groups that charged that the decision was based on back-room 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 per second during the dry season, from April to June, and 20 the remainder of the year.

To accomplish that, Tampa and Swiftmud agreed to split the cost of about $40 million in projects to boost river flows, including changes to the Sulphur Springs pumping station.

But the manatee issue has put those efforts on hold, for now.

Environmentalists say it's an example of the lower Hillsborough's delicate ecosystem.

"It's a difficult balancing act," the EPC's Thompson said. "Sometimes there is a conflict."

Reporter Christian M. Wade can be reached at (813) 259-7679.

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