Replacing an Aging Wastewater Treatment Plant
With equipment reaching the end of its useful life and steel structures degrading from the corrosive action of the nearby salt water, member-owned Gasparilla Island Water Association knew it was time to replace its aging wastewater treatment plant. The unusual characteristics of its location made an already challenging undertaking even more complex.
Situated off Florida’s southwest coast, Gasparilla Island is home to approximately 1,700 residents, all customers and owners of the wells, pumping stations, storage tanks and wastewater treatment facilities that serve the Island. While many are full-time residents and business owners, most are second-home owners who enjoy escaping the colder northern climate during the winter months.
The small barrier island—it’s barely a mile wide at its broadest—means limited space: GIWA leases a modest area within the island’s private golf course, which set the parameters for the new facility. The golf course owner is also a strong ally, consuming about 80% of the effluent collected and treated at the facility.
Replacing an operating treatment plant is a big undertaking in any circumstance, but because of the limited space, GIWA has been building the new plant within its same footprint, dismantling outdated facilities in phases as the new structures are complete.
“We’re keeping our existing plant serviced and operating, while fitting the new facility around it in a very tight area,” said Utility Director Bonnie Pringle, an industry veteran of more than 40 years and a board member for the Florida Rural Water Association. Pringle retired in February 2022.
Construction is further complicated by the limitations of the causeway from the mainland, which can only handle vehicles under 36,000 pounds. GIWA was forced to build its own temporary bridge to move heavy equipment and material for the new plant. The adjacent waterway’s popularity means the bridge’s center section must be removed during the busy season, whereby heavy loads can only be moved onto the site between May and November. And, with residents expecting to enjoy their leisure time, construction has also been carefully timed, with some phases planned for summer months and others, when necessary during the season, scheduled after hours.
“We’ve managed construction very carefully, saving the heavy work for the off-season and doing things like pouring concrete in the evening when necessary,” said Pringle. “Nighttime work drives up costs, so we try to limit it, but our members’ quality of life remains our priority.”
A CoBank borrower since 1993, GIWA’s new plant called for a $16 million term loan in addition to an established operating line of credit. The four-year, staggered construction schedule is now at the halfway point, and will be well worth it for GIWA’s members: the new treatment plant can process over 700 thousand gallons a day, well above their needs with no significant population growth anticipated. Output will also surpass current water quality regulations.