It appears Longboat Key’s June sewage-line break in mainland Manatee County wasn’t as big as the town originally estimated, according to a state regulatory agency.
The Florida Department of Environmental Protection said last week it estimates the leak was about 17 million gallons, down from the town's initial estimate of 25.8 million gallons.
FDEP spokeswoman Shannon Herbon said the revised estimate is based on average flow data received from Longboat Key and similar data from the Manatee County end of the pipeline that runs under Sarasota Bay between the mainland and the island.
“Today, the department received a topographic survey to aid in the evaluation of the overall impact of the wastewater spill to the mangroves in the area,” Herbon wrote in an email. “We are now reviewing that information and will incorporate it into the overall investigation.”
The state's investigation into the sewage break is ongoing.
“We expect to have enforcement actions, including penalties, finalized in the next few weeks,” Herbon wrote.
U.S. Rep. Vern Buchanan, R-Florida, tweeted about the FDEP's lower estimate.
Last month, Town Manager Tom Harmer said the initial report of up to 25.8 million gallons spilled was a high estimate based on normal daily flows.
The town has contracted Berkeley Research Group to estimate the total discharge amount and to determine the cause of the break, which took place underground and about 100 yards inland from the shoreline of Sarasota Bay. Harmer said the town is waiting to hear back from BRG.
On June 29, town officials reported to state regulators an estimated 25.8 million gallons of untreated sewage might have spilled in the break of the 20-inch pipe, but instrumentation glitches began showing up days earlier, possibly indicating trouble before the break was confirmed.
Water testing by contractor Environmental Science Associates found no evidence of human waste in Sarasota Bay near the point of June’s sewage break. The town is expecting a draft report on the environmental testing soon.
The town is also moving forward with plans on a redundant pipe project, retaining Carollo Engineers, Inc. to begin conversations with state and federal agencies on planning and permitting. The pipe was built in 1973 but was inspected in 2015-16 and given years of estimated life remaining.
The pipe gathers sewage from the entire town, pushes sewage east from a pumping station on Gulf Bay Road underneath Sarasota Bay and terminates at a treatment facility north of Conquistador Parkway in Bradenton.