Thursday, March 30, 2017

Orleans moving ahead with exciting work on Nitrogen Removing Oysters

This article outlines the discussion around Orleans funding of a project on studying oysters as a tool for nitrogen removal. Despite discussion, the project was funded for another year. 

You can see the original article here.

Selectmen Digest Report On Nitrogen-Removing Oysters 22 March 2017

By: Ed Maroney

ORLEANS, MA — He who pays the piper should call the tune – even if it's the sewer piper. But some feel the piper – the regulators and consultants – are making the town dance instead.

Things aren't that simple, however.

In recent years, Orleans has explored alternatives to widespread sewering to meet nitrogen reduction goals for its waters. Among the alternatives outside of downtown have been low-tech and less expensive options such as oyster filtration. But the town is still hearing “prove it” from the state Department of Environmental Protection, and that proof comes at a cost.

At last week's board meeting, Selectman Mark Mathison voiced concern about the town's role as banker for experiments that may also benefit many other parties. He spoke March 15 after a presentation by AECOM environmental scientist Paula Winchell about results of the oyster pilot project in Lonnies Pond and its proposed second phase.

Winchell said testing of oysters from last year's experiment showed that 10.3 percent of dry tissue weight was nitrogen, a finding comparable to similar work done in Pleasant Bay. Almost 26 kilograms of nitrogen was removed via the oysters. The experiment deployed 200,000 oysters in 800 bags; about 127,000 were two-inch and the remainder one-inch.

The town's target for nitrogen reduction in Lonnies Pond is approximately 300 kilograms a year, and the total maximum daily load allowed is about 0.82 kilograms a day. The proposed second phase of the project would ramp things up with 3,000 bags holding 600 one-year oysters each and 4,500 bags with 250 two-year oysters each. There would be four one-acre “plot” floats of oysters: two over deeper water and softer bottom than last year's experiment, one in a location similar to last year's, and another over the same area used last year. This last would continue to add deposits to the bottom area where the initial study took a first look at denitrification.

Mathison asked if the town was committing significant money to an aquaculture project that would not provide solutions for all the town's ponds and that might not win the approval of state regulators.

“Why are we asking the taxpayers of Orleans to fund these scientific investigations?” he said. “They should be done in the research field.”

To Mathison's point that last year's study had confirmed what was already known – that oysters can aid in denitrification of ponds – the town's water quality consultant, Mike Domenica, said that the question is whether such a program can be managed over time so “DEP can bet on it.” More work is needed, he said, to determine whether the process is cost-effective per kilogram removed. “We can't put all the burden on one technology,” he cautioned.

Mathison called for more details on aquaculture plans. “What's the impact on moorings, boating, swimming?” he asked. “Not only do we need something demonstrated to DEP, but to the taxpayers of the town.”

“All of us,” Domenica said, “are aware of the elephant in the room, the long-term impact, the acceptability to abutters, growers” and marketing the grown shellfish. “This is what Year 2 will be,” he said, a look at those concerns.

“I think DEP should be paying for some of this,” Selectman Jon Fuller said. “Orleans is paying for everything.” Even so, he was reluctant not to proceed with Year 2 and lose the progress already made.

The board was to vote on releasing funds for further work in Lonnies Pond at its meeting last night, after the paper's deadline.

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