In January, NYDEC and the Long Island Regional Planning Council (LIRPC) released a Conceptual Draft Scope for the Long Island Nitrogen Action Plan that sets forth goals, planning structure and tentative schedules & tasks designed to reduce the levels of nitrogen in the waters around Long Island. A series of public meetings were held in early February to present the plan and take public comment. Seatuck recently submited its comments, which can be downloaded here.
One key component of Seatuck's comments is a recommendation that the NYDEC and LIRPC include an effort to increase circulation and ocean exchange in the Great South Bay and other estuaries. Such an effort would seek to mitigate the impacts of nitrogen in the interim period before nitrogen inputs can be fully reduced. The following is an excerpt from Seatuck's comments on the subject:
High levels of nitrogen and pathogens have severely impacted Great South Bay and the rest of the South Shore Estuary Reserve. Diminished clam populations, harmful algal blooms and closed swimming beaches evidence some of the worst water quality problems on Long Island. Against this backdrop, the positive ecological effects of the 2013 Bellport Inlet (and the 1993 Little Pike’s Inlet before that) have provided a glimmer of hope that these conditions are not permanent and can be reversed.
Inspired by the story that’s unfolded over the past three years in eastern Great South Bay, Seatuck has been exploring opportunities for expanding the positive effects of greater ocean exchange. While recognizing that the ultimate solution to improved water quality starts with eliminating pollution and mindful of the adage that the “solution to pollution isn’t dilution”, we nevertheless think there is ample reason to support a comprehensive effort to increase ocean exchange in Great South Bay and beyond.
First, work already underway, as well as many of the actions contemplated in the LINAP, won’t produce tangible benefits for years and decades in the future. Source reductions from sewage treatment plants and on-site treatment units, for example will take many years to achieve. And even if these inputs could be stopped today, our south shore bays will still be impacted by legacy nitrogen already in the ground for another 5 to 50 years. As Bellport Inlet has demonstrated, greater ocean exchange would help to mitigate these impacts in the interim.
Second, improving water quality through increased ocean exchange would give the estuaries a head start in recovering in the years and decades before the spigots of pollution could be turned off. Eelgrass beds, clam populations and schools of forage fish would benefit from the increased influence of clean ocean water. Lower overall nitrogen levels would also reduce adverse impacts to salt marshes, giving the precious remaining acreage a chance to hold (and gain) ground –especially in the face of rising sea levels– until nitrogen inputs can be reduced.
Finally, there is reason to conclude that even with nitrogen pollution under control the Great South Bay and other portions of the South Shore Estuary Reserve will continue to suffer water quality problems resulting from stagnation. Historically, breaches in the barrier islands regularly opened and closed, allowing greater ocean exchange and tidal flushing throughout the estuary. However, roadways, bridges and other infrastructure, as well as barrier island policies, now combine to nearly eliminate this natural process. The result is that some areas of the South Shore Estuary Reserve, including western Great South Bay and (until recently) Bellport Bay are flushed at rates far below historic levels.
For these reasons, we urge the State to conduct a comprehensive assessment of options for increasing ocean exchange and tidal flushing in the Great South Bay and other estuaries around Long Island. We encourage the State to consider and assess the following: Improve barrier island breach policy; Improve flow through Smith Point Bridge and Wantagh Causeway; Enhance circulation; Augment ocean input; and Increase efficiency of Fire Island Inlet.
Additional details about the proposed actions are contained in Seatuck's full comments.