Suffolk County is moving forward on its goal of eventually requiring all single-family homes to have advanced individual on-site wastewater treatment systems that will reduce nitrogen loading to groundwater and surface waters.
The Suffolk County Legislature last week approved an amendment to the sanitary code adding Article 19, which gives the County Department of Health Services the authority to promulgate procedures, protocols and standards for the use of innovative and alternative on-site septic treatment and disposal systems.
The new Article 19 authorizes the first major change to residential wastewater treatment technology since 1973, when a septic tank was added to a leaching pool, according to the county’s director of water quality.
Traditional individual septic systems, which do not treat waste to reduce nitrogen at all, account for 76 percent of Suffolk’s wastewater flow, according to county officials. An estimated 360,000 homes use conventional private septic systems that do not reduce nitrogen. Wastewater from these systems has been identified as the single largest contributor to nitrogen in Long Island waters and solutions need to be identified, County Executive Steve Bellone said in a press release on Friday. Excess nitrogen has resulted in hypoxia and harmful algal blooms in our estuaries, and has impaired eelgrass beds, wetlands, and shellfisheries and diminished our coastal resiliency, Bellone said.
The county is currently testing six advanced treatment systems in 19 homes throughout the county which were chosen by lottery in 2014. It is about to begin testing eight more systems, said County Legislator Al Krupski. The county has selected another 20 homes from all 10 towns to participate in phase two of the program. The systems include free installation, monitoring and maintenance for five years. In addition three vegetative wetlands systems are also being tested, Krupski said.
“Article 19 provides the framework for testing and piloting and eventually approving these advanced systems for general use,” Krupski said.
“The million-dollar question is: where and what’s the mandate,” Krupski said. “Is for new construction, replacement systems, failed systems? And what authority are the towns going to have to dictate what type of system is required and under what circumstances? Article 19 provides that framework.”
Kevin McAllister of Defend H2o says he’s concerned that the county isn’t going to be bold enough when it comes to treatment requirements.
Since the code itself doesn’t set performance standards for the advanced systems other than requiring “a greater reduction in total nitrogen” than conventional on-site wastewater treatment systems — which don’t effectively reduce nitrogen at all — the actual performance standards will be set by county health department staff. The staff is currently saying the standard will be set at 19 mg/l, McAllister said in a June interview.
Conventional systems have a total nitrogen output of 50 to 60 mg/l, so 19 mg/l is a significant reduction, but existing technology allows for a far greater reduction, to under 10 mg/l, according to McAllister.
“It’s an evolving process,” Krupski stressed today. “And it’s rapidly evolving. We’re just starting out.”
The county legislator said a major concern he’s had is the potential that the availability of advanced treatment systems may have for increasing development density, which Krupski says the county must guard against. The availability of community sewering allows for higher development densities. He said that he and South Fork Legislator Bridget Fleming worked to ensure that language was included in the code to make it clear that the availability of advanced individual treatment systems is not intended to allow higher development densities in currently on the East End.
