County officials say Lake Manatee Dam leak not responsible for Braden River flooding

MANATEE COUNTY, Fla. — More than a month after Tropical Storm Debby ripped through the area, Manatee County officials are trying to educate the community about how the Lake Manatee dam works — and why they say it is not the cause of the severe flooding that has destroyed so many homes.

Tropical Storm Debby dumped up to 17 inches (43 centimeters) of rain in parts of the county, prompting rescue efforts that forced more than several hundred residents to evacuate their homes or vehicles.

Many community members blamed county officials for the way water was released from the dam during Hurricane Debby, forcing county commissioners to order an independent investigation.

“When you’re looking for answers, if you’ve experienced this disaster in your home, you want to find answers that just make sense to you,” Natural Resources Director Charlie Hunsicker said Wednesday morning. “But I can tell you with 100 percent certainty that the Manatee River basin and the discharge from the dam did not move through the Braden River basin and cause flooding there.”

County officials remained steadfast that the dam operated as designed during Debby. Local media were invited Wednesday to tour the dam and ask leaders questions about its operation.

Lake Manatee supplies about two-thirds of Manatee County’s drinking water, about 12 billion gallons per year. County workers operate the dam 24 hours a day, monitoring water levels and flows in and out.

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“This structure was built for one purpose only: to create a reservoir on the Manatee River to provide fresh water to the growing Manatee County,” Hunsicker said.

The lake holds about six billion gallons of water, but Tropical Storm Debby added another 17 billion gallons of water. The top of the reservoir is 50 feet high, but it is designed to hold 38 to 42 feet.

During the rainy season the lake level remains at about 38 feet.

“We got the lake down to 36 feet before Debby. That’s very typical. That’s where we went with Irma. That’s about where we went with Ian,” said Deputy Director of Public Utilities Katherine Gilmore. “That’s a normal level when you know you’re going to get some rain.”

Operators say they cannot lower the lake’s water level too much without jeopardizing the county’s water resources, especially during the dry season.

“There’s always going to be a storm that exceeds your design standards,” said Manatee County Deputy Administrator Evan Pilachowski. “So if another event happens, if we get 54 inches of rain, yes, we’re going to have flooding. There’s just no way to prevent that with the infrastructure that’s been built.”

Residents of lower-lying towns blame the water leak from the dam, the timing of it and the manner in which information was conveyed to the victims.

“The river was receding on its own, but not because the Manatee River was causing it to recede,” Hunsicker said.

Maps showing water flow in each watershed across the county have not been updated since the early 1980s.

Many community members also blame the county government for continually approving more and more developments.

“I think the commissioners will certainly be talking about this when we come to the revision of the COMP plan, so they will certainly be considering it.”

“There’s always going to be a storm that exceeds your design standards. So if another event happens, if there’s 54 inches of rain, yes, we’re going to have flooding. There’s just no way to prevent that with the infrastructure that’s been built.”

During Debby, the dam’s emergency spillway was opened because one of the three main spillway sluices is not operational and maintenance work is underway on it.

Maintenance work is not typically carried out during the rainy and hurricane season, but workers say this was due to supply issues.

“When the next major rainfall event comes, we can’t prevent it from happening,” Pilachowski said. “We can certainly improve communication with residents about where we expect impacts.”