Tisbury board of health drafts new nitrogen regulations

The Tisbury board of health unanimously approved their nitrogen regulations for the Lagoon Pond and Lake Tashmoo watersheds, requiring property owners to install enhanced denitrification systems. Lake Tashmoo, shown here. — Nelson Sigelman

The Tisbury board of health will discuss a new set of draft nitrogen regulations at 4 pm, Tuesday, August 9, in the Town Hall Annex in Tisbury. Board of health chairman Jeffrey Pratt said he was not sure if the board would take a vote prior to speaking to Tisbury selectmen and the town administrator.

The board of health is scheduled to present the regulations to the Tisbury board of selectmen on Tuesday, August 16, at the Tisbury Town Hall.

Despite the fact that the board will discuss the new regulations, which carry significant new costs, Mr. Pratt was unable to provide The Times with a copy on Tuesday. “We’re not releasing the draft of nitrogen regulations just yet, but we do have a new version, and we are very excited about it, and we think we’ve solved a lot of the concerns expressed during the public meetings,” Mr. Pratt said in a phone conversation with The Times Tuesday.

A prior version of the new regulations carried hefty mitigation fees for anyone building in the Lake Tashmoo and Lagoon Pond watersheds.

Last week, health agent Maura Healey told The Times, “I believe what they’ll do is vote against the mitigation fee, but move forward with the best available technology and advanced treatment systems.”

Enhanced denitrification technology, according to the board of health’s first proposed regulations,means an on-site innovative denitrification wastewater disposal technology approved by the Board of Health that, compared to a Title 5 Septic System, is designed to remove a greater amount of nitrogen, and includes both in-home technologies, such as innovative denitrifying toilets, and in-ground technologies.”

Mr. Pratt said if a homeowner’s current septic system failed, for example, or if they increased the number of bedrooms, then they would be required to put in an advanced denitrification system. New homeowners would be required to put in advanced systems as well. He said if a home’s septic system could be tied to the town sewer system, then they would not be required to invest in an advanced system.

Asked what this would cost homeowners, Mr. Pratt was unsure. “There would be a cost increase over standards. I’m embarrassed to say I don’t know the answer to that,” Mr. Pratt said. “I do know they cost more money, but don’t know exactly how much.”