Committee hears presentation on advanced on‑site wastewater systems and local upgrade programs

Roxanne Groover, executive director of the Florida On‑site Wastewater Association, told the Senate Committee on Environment and Natural Resources on Oct. 12 that advanced on‑site wastewater systems available in Florida can reduce nitrogen entering groundwater and surface waters by roughly 50% to 85% at the end of pipe.

The topic matters because on‑site systems treat about one‑third of the state’s wastewater while receiving, Groover said, “less than 1% of the funding that’s available.” Committee members pressed staff and the witness about phosphorus, emerging contaminants such as PFAS, costs, and how grant programs are structured to encourage upgrades instead of conventional replacements.

Groover opened by urging the committee to focus on advanced treatment rather than “conventional legacy systems,” saying advanced systems have been used in the state for more than 20 years and that multiple technology classes are in use. “We have 3 different types of systems that are often used to be able to treat nitrogen reducing communities,” she said, and summarized three regulatory/technology pathways in Florida: NSF certifications (often referenced as NSF 245 and related NSF standards), state performance‑based approvals or the Department of Environmental Protection’s innovative process, and the in‑ground nitrogen reducing biofilter (INRB) developed through a state study.

She described technology families—suspended growth/aeration, submerged fixed film, membrane/media filters, and sequencing batch reactors (SBRs)—and explained typical nitrogen removal ranges for each: she said some systems achieve roughly 50% reduction while others reach up to about 85% at the end of pipe. Groover also said that dispersal into soil provides additional treatment, noting an “additional 15% of soil treatment after these systems.”

Committee members asked technical and policy questions. Senator Gayle Harrell asked, “Do any of these systems work for phosphorus? And how about PFAS?” Groover replied that phosphorus‑removing technologies exist beyond those covered in her slides and that PFAS is an emerging concern the industry and NSF committees are studying. Senator Ben Broder asked how much nitrogen a traditional septic tank removes; Groover answered, “Less than 30%.”

Groover outlined elements of Florida’s regulatory oversight: many NSF‑certified systems require a Florida professional engineer’s certification of tank integrity, an operating permit, and enrollment of a maintenance entity (residential systems typically inspected twice a year; commercial systems more frequently). She said performance‑based systems always require a PE design and can be permitted under site‑specific allowances that may reduce drain‑field footprint or increase permitted flows. The INRB, she said, was developed with legislative support as a passive, non‑proprietary option: the unlined INRB requires no PE design and no operating permit but must be tied to the property title so future buyers are informed.

Groover gave examples of local grant programs that fund upgrades. She said Volusia County’s spring area program initially offered $10,000 per system and had asked to increase that to $15,000 to cover the incremental cost of advanced systems for eligible homeowners. She said Hernando County offered up to $7,500 per installation and that Brevard County’s “Save Our Lagoon” program had a $29 million budget for septic upgrades and reported about 38,000 pounds per year of nitrogen reduction from on‑site system upgrades; Groover said about 287 homeowner upgrades were completed under that effort.

On cost and market response, Groover said manufacturers often rework or add components—recirculation loops, submerged media, or supplemental carbon sources—to achieve higher removal rates, and that once Florida signaled a market (for example by accepting NSF standards in specific programs) manufacturers sought Florida listing and PE certification. She also said some manufacturers have chosen to market the higher‑performing unit when the cost difference between mid‑ and high‑performance models is small.

Groover and senators agreed that more monitoring and data would help, especially for passive systems such as the INRB. She said the absence of an operating permit and required maintenance visits for unlined INRBs has made long‑term sampling and independent performance verification difficult, and she encouraged incentives for homeowner participation in monitoring programs.

The committee did not take formal action on the presentation; the discussion centered on technical clarifications, grant design, and whether state programs should incentivize higher‑performance units and monitoring.

Committee members thanked Groover for the briefing and noted the importance of advanced on‑site options in areas that are unlikely to connect to sewer systems.

Groover offered to provide follow‑up information to members and committees about PFAS work at NSF and about local programs’ results.