Gathering funding from a variety of sources and permission from a batch of state and federal agencies, the town of Longboat Key aims by 2024 to begin building a second underwater sewer line to link island businesses and residences to Manatee County’s mainland treatment plant
The project, estimated to cost around $24 million, won’t be a one-and-done effort though it is designed to last decades, said Public Works Director Isaac Brownman.
Fast-tracked from a 10-year goal to the town’s five-year capital improvement plan after a mainland-side break in 2020 that spilled millions of gallons of town sewage, the project will build redundancy into a sewer system that hasn’t previously included that luxury. Under current thinking, the new two-mile pipe will take over as the primary link to Manatee County while the original pipeline is kept, monitored and maintained in reserve.
“If you asked us, what do we lose sleep over at night?’’ Town Manager Tom Harmer said. “Having a failure in the one line that goes to the mainland carrying our wastewater is the top of that list.’’
Ultimately, the project will have worked through a permitting process made more rigorous by the delicate nature of Sarasota Bay itself. The first phase of the project, which takes place largely underground between the bay's shoreline and 53rd Street in Bradenton could be complete by summer of 2023.
Before final designs and construction plans of the new pipeline are set, a preliminary project will likely be underway from near the Manatee County shoreline of Sarasota Bay north to a point where the county monitors the flow of inbound sewage from the town.
It's near the point at which Longboat Key's underwater pipe makes landfall on its way to Manatee County's treatment plant, and the point where the 2020 break took place.
In the next 12 months, the town intends to reline that 1973-era 20-inch iron pipe with a material called high density polyethylene, essentially creating a contemporary pipeline within the structure of the one built when Richard Nixon was president.
Brownman said the original pipe was built to handle a capacity greater than today's Longboat Key could ever produce.
"The size of it was designed for the ultimate build-out of the island before the downzoning occurred,'' Brownman said, referring to a 1984 decision to limit island density, changing a development trajectory that would have likely made modern-day Longboat likely a much more crowded place. "So it was actually built for more capacity than it will ever handle. So that's why in this case, which is pretty handy, we're able to do the slip lining, which will reduce the effective internal diameter, but our engineers have all looked at it and said, 'you're still going be able to carry the flows from the island.' ''
With that pipe relined, it's expected to operate into the 22nd century.
"Right now people say it's about a 75- to a 100-year type of material, and it doesn't degrade,'' Brownman said.
Pre-construction work is already under way, along with some design work and preparations for access to the site. Formal permission is being sought from private land owners along Long Bar Pointe, adjacent to the work site. While work is underway to reline that pipeline, Brownman said, service to island residents shouldn't be interrupted, but work crews will likely construct an above ground bypass pipeline first.
The town has already landed $1.25 million in state funding from the last budget session and is waiting for word from Tallahassee on $800,000 addition in the still-unsigned state budget on Gov. Ron DeSantis' desk.
The town is already two to three years into the process of permitting the new pipeline under Sarasota Bay, which crosses from around Gulf Bay Road to Long Bar Pointe in a narrower-than-normal stretch of the waterway.
Sarasota Bay is designated one notch below the most-stringently regulated class of waterway, Class I, which is set aside for sources of drinking water. The town has in hand a permit from the Florida Department of Environmental Protection and expects one soon from the U.S. Army Corps of Engineers.
"State and federal permitting agencies are very much involved in all that determination because it involves a Class II state waterway, which is also a national estuary and very sensitive environmentally,'' Brownman said. "So there's a lot of scrutiny in that.''
The town also must work with Florida's Office of State Lands to demonstrate the town will be able to secure easements from private landowners on the mainland to proceed.
Brownman said once the Army Corps permit is completed, the town can move ahead on design and make decisions on what kind of contract to seek to get the work done.
In the meantime, the town has been socking away money where it can to pay the tab. At least half of the town's $3.6 million American Rescue Plan Act money will go to the sewer line project, with potentially more from that source.
"We have the other $1.8 million that would go towards (flooding and stormwater mitigation) or the wastewater line, depending on Commission final approval and direction there,'' Harmer said.
The town has also worked with U.S. Rep. Vern Buchanan (R-Longboat Key) for another batch of federal funding, about $3 million, from other sources. The town this year also launched an incremental increase in water and sewer rates in anticipation of borrowing not only for the pipeline project but also to replace water pipes in Country Club Shores.
Beginning in 2022, the town's water and sewer rates were reset to begin climbing to help pay for the sewer line and the Country Club Shores work. From an average bill of $74.75 in 2021, bills will climb to $105.30 by 2029. With the additional revenue, the town can afford to borrow the remainder of what it needs for the two water and sewer endeavors.
"The utility rate plan was built assuming that we would have to pay all of that cost with some sort of debt issuance that the ratepayers would have to repay using this rate model over a, say, 30-year period,'' Brownman said. "And any way we can draw that down and offset, that is what we're looking to do because of the size of the project and its magnitude.''