Tisbury proposes new development fees to offset nitrogen loading

Under the proposal, an annual mitigation fee would be applied to all new developments within the Lake Tashmoo and Lagoon Pond watersheds.

The Tisbury Board of Health is looking to address nitrogen loading in Lagoon Pond and Lake Tashmoo. — MV Times

The Tisbury board of health expects to hold public hearings in mid-June on proposed new wastewater regulations intended to reduce excess amounts of nitrogen entering Lake Tashmoo and Lagoon Pond by imposing hefty fees on any new development, including additions and renovations, in the Tashmoo and Lagoon watersheds.

Under a “no new net nitrogen” policy, property owners would be financially responsible for mitigating the effects of wastewater-based nitrogen that enters the groundwater through an annual fee, based on metered water usage and an estimate that it costs the town $300 to remove a pound of nitrogen from wastewater.

For example, based on average water usage and use of a Title 5 septic system, the owner of a new three-bedroom home in either watershed would pay a fee of $3,200. Under the proposed fee schedule, the charge could be reduced to $2,100 with the installation and use of an enhanced denitrification system, designed to remove nitrogen from the wastewater. The use of denitrifying toilets in combination with advanced systems could reduce the annual fee to $320.

Under the draft regulations, the Board of Health defines new development as “any new structure, the renovation of, or addition to any existing structure and, in the case of commercial and industrial developments, also includes any increase in intensity of use, or any change in use, which generates an increase in human wastewater flow for disposal.”

Application of the fee will be triggered by the filing of a building permit, and would cease either after 20 years, when the development is connected to the town sewer system, or when the town successfully removes enough nitrogen to certify water quality standards.

The regulations stipulate that the collected fees could not be used for general purposes: “Mitigation Fees collected shall be used solely to remediate, mitigate, reduce, or eliminate nitrogen pollution in Lagoon Pond and Lake Tashmoo and in the portions of Lake Tashmoo and Lagoon Pond Districts that lie within Tisbury town borders.”

‘The first step’

The Tisbury board of health is an elected three-member board made up of Michael Loberg, Jeffrey Pratt, and Malcolm Boyd. In a telephone conversation Friday, chairman Michael Loberg, husband of Tisbury selectman Melinda Loberg, said depending on what the board hears at the public hearings, the new regulations could go into effect late this summer. “I think everyone sees the public hearings as a valuable opportunity to talk about the nitrogen issue, and I think the hearings are an opportunity to make the regulations better,” he said. “I don’t think anyone will be in a hurry to push that process. I think we will hold hearings until we think we’ve heard everything.”

Mr. Loberg said the proposed regulations have been in the works for about five months. The board has worked on them in conjunction with the Tisbury Wastewater Committee and with technical support from the Martha’s Vineyard Commission, he said.

He said the board of health has the authority to implement the new regulations without seeking approval at town meeting, citing a moratorium the board of health passed in 1975 on construction along Tisbury’s inner harbor to address a sanitation issue.

“We see the nitrogen issue the same way,” Mr. Loberg said. “We think it’s a health issue. It doesn’t require a moratorium, it just requires that any new development proceeds in a way that’s responsible with respect to adding more nitrogen to the pond.”

He said the regulation is an attempt to keep the nitrogen-loading problem from getting worse; the idea is to maintain the current health of the pond.

“What we want to make sure is that in our attempt to solve our nitrogen problem, we don’t wait so long that the ponds get worse than they are now,” Mr. Loberg said. “Some of the ponds on the Cape are in the condition that they can no longer be part of the solution. Our ponds still have some health, and what we want to do is make sure that things don’t get worse.”

He said that 11,000 pounds of nitrogen is currently going into the ponds every year, and if, for example, the Tisbury planning board said the housing stock would increase by 15 percent, it would add another 5,000 pounds of nitrogen.

“We’re not trying to remove the 11,000; we’re just trying to keep the 11,000 from becoming 16,000,” he said. “This is where you start.”

He said people constructing new homes have the ability to install nitrogen-reducing systems, and in turn pay a smaller fee.

“It starts a dialogue about how people want to behave in terms of their nitrogen responsibility,” Mr. Loberg said. “It’s tempting to think that when you’ve put in a septic system and you’ve dealt with the sanitation issue, that you’ve done all you need to do for the town.”

He acknowledged the proposed regulation doesn’t address the whole problem. He said the Tisbury wastewater committee is charged with tackling the larger issue — the 11,000 pounds.

“We felt that it was within the purview of the board of health to make sure that the nitrogen problem does not get worse, so that the ponds are not threatened more than they are now,” he said. “That’s not the whole job, but I have no trouble saying it’s the first step in the job.”

‘Potential to damage’

The new regulations are based in part on the Massachusetts Estuaries Project (MEP) reports for Tashmoo and the Lagoon. The MEP studies, a joint project between the University of Massachusetts School of Marine Science and Technology and the state Department of Environmental Protection, studied coastal salt ponds across the state and set limits for nitrogen loading in each pond.

According to the MEP reports, for Lake Tashmoo and Lagoon Pond, 6,435 and 13,016 pounds, respectively, of the current nitrogen load must be removed in order to maintain sustainable water resources, based on the assumption that no new nitrogen will enter the waters as a result of new development. The MEP reports that human wastewater accounts for 80 and 76 percent of the overall controllable nutrient loading in Tashmoo and the Lagoon.

“The Town of Tisbury’s population has grown to the point where the wastewater treatment infrastructure in place lacks the capacity and/or capability to remove sufficient nitrogen to assure that Tisbury’s ponds and other water resources meet applicable water quality standards as well as provide for the safety of those using those resources,” the proposed regulation states.

The regulations state that excess of nitrogen in town waters has the potential to damage human health, especially in infants, young children, pregnant women, and those with compromised immune systems who consume nitrates in excess of the established Safe Drinking Water Standards.

The excess nitrogen also affects the health of aquatic plant life, “destroying wildlife habitat and degrading the waters for shellfishing, recreation, and other public purposes,” according to the regulations.