He came to relax; he ended up taking on the Island’s nitrogen problem

John Smith uses innovative technology to retrofit septic systems and stamp out nitrogen loading in Island ponds.

KleanTu employees Michael Lipinsky, left, and Jonathan Devaney, at Goodale’s assembling NitROE systems. — Courtesy John Smith

John Smith’s plan was to transition from a 40-year career in engineering to spending more time at a home he owns in Edgartown, but once he got here and learned about the Island’s nitrogen pollution problem, his plans began to change.

Smith has owned a home in Edgartown for the past 25 years, and has been living mostly full-time on the Island for the past four years. As he began spending more time on the Vineyard, Smith became more aware of how excess nitrogen was harming the water quality of the Vineyard’s ponds and estuaries.

It’s been three years since Smith, president of KleanTu Wastewater Treatment Technologies, teamed up with the town of Tisbury and secured a grant to install 10 innovative NitROE wastewater treatment systems, and with promising data, the company is inching closer to general permit status.

Speaking to The Times by Zoom, Smith said KleanTu was able to install its new tech with a pilot permit from the Massachusetts Department of Environmental Protection. Smith said the first 10 systems were then monitored for the next year, to test nitrogen levels. 

“The results were such that we were getting levels of nitrogen lower than the current alternatives being used and applied … We started getting numbers lower than them. Significantly lower,” Smith said.

According to Smith, average nitrogen levels in septic treatment systems is 19 parts per million (ppm). KleanTu’s system is showing data in the 10ppm range, and some even as low as 5ppm.

The system works by retrofitting a NitROE tank to an existing septic system, between the existing septic tank and the leaching field. The NitROE tank contains a rock-filled aeration chamber and a woodchip-filled denitrification chamber. The aeration chamber takes organic nitrogen and ammonia and turns it into nitrate. The second chamber then turns the nitrate into nitrogen gas that is released harmlessly, and with no odor, into the atmosphere.

With Smith on the Island and the NitROE tanks crafted at Goodale’s, KleanTu is very much an Island venture. “You may say KleanTu started out as an Island-grown company, which is pretty cool,” Smith said.

Eutrophication — the buildup of excess nutrients — in ponds is the main culprit behind algal blooms, rapid increases of algae in freshwater and saltwater that come to dominate an ecosystem. Most estuaries are dealing with nitrogen loading, which enters the pond through rainwater, decomposition of biological matter, animal waste, septic sources, or fertilizer, according to the foundation’s website. Phosphate, nitrate, and ammonia are other nutrients known to cause blooms. Excess nutrients cause blooms, blooms cause oxygen starvation, and oxygen starvation harms other organisms in the ecosystem.

The public-private partnership has been fruitful. In three years, KleanTu has installed NitROE systems at 14 locations on the Island, and four in Falmouth.

Former selectman Melinda Loberg praised the NitROE system in a phone call with The Times. Loberg worked with Smith, the Martha’s Vineyard Commission, the Tisbury board of health, and other stakeholders to get the systems installed. “It was a nice project because we could prove the technology worked, and we could make it an Island venture,” Loberg said.

Loberg added that the town was trying to solve the nitrogen issue in the town’s ponds. She said the only real problem solver was to build sewers, which would be expensive. Instead Smith and KleanTu came along to offer a cheaper, innovative solution. “It’s really a game-changer for the Island, and I feel very fortunate to be a part of it,” she said.

With two years of solid data, MassDEP has allowed KleanTu to advance to a provisional permit, allowing it to install up to 50 units. Installation times vary for the systems, but Smith said the installation for an individual home for just the NitROE system is two to three days. 

With successful test systems on the Island, KleanTu began getting interest from Falmouth.

Smith said the pandemic has not hurt his business as much as others, but one of the biggest challenges his company faced was with an installation at the College Light Opera Company. 

The construction for the Falmouth institution’s 6,000-gallon-per-day NitROE system was set for February, but was delayed until June. While it’s installed, Smith said, KleanTu still has to wait until this year, when students return to the campus, to gather data, but he’s confident it will work because a larger,three-year-old NitROE prototype at the Massachusetts test center has been reducing the average nitrogen to 3 to 5ppm, which Smith says is as low as anyone can get.

After two to three years of operation continuing to show good results, Smith said, KleanTu can get general permit status, which allows systems to go in without as much state oversight and monitoring, since they are deemed a proven technology.

When asked why every eligible home on the Vineyard doesn’t have a NitROE system, Smith said his company’s technology is part of a shift to decentralized wastewater treatment from its longtime centralized approach. He also said there’s a disconnect between homeowners and alternative treatment systems, but is confident that with the years of proven data KleanTu has gathered, there will be more interest.

“One of my partners has a great saying — we just need to get more dots on the map,” Smith said. “It’s not going to be a leap of faith, it’s going to be the data and the information and the comfort level people have to go to that next step.”

A conventional Title V septic system can cost around $15,000. Smith said a NitROE tank adds an additional $13,000 to $15,000, which is in line with other alternative systems. NitROE’s advantage is that it can be retrofitted to an existing system.


  1. Super news!! Cleaning up our ponds is a huge job and these new add ons sound effective and somewhat affordable. Although they are way too expensive for many islanders.

  2. A great idea, but lets give Anna Edey some credit here. She has been banging her head against the walls of bureaucracy at least since I arrived here in 1986.

    • I agree with what Don said about Anna Edey. She told me about her system many years ago and it is a proven system as well her system should be used as well.

  3. And ? How often do you have to change the wood chips and at what cost! That goes for the rock filled NitROE chamber. I would think there is a time limit that certain liquids can run through wood chips and over rock before there is gunk build up.

    Please don’t just describe the perfect picture without the nitty gritty.

    • dana– as you know, title 5 has plenty of nitty gritty also .
      One article can’t get into all the details.

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