For the most part, the now-mandated low-nitrogen septic systems being installed on eastern Long Island work as promised. According to a report from Suffolk County government, about 550 of them have been installed and have been cutting the contaminant flow by almost 85 percent in the best-performing units. The big if is whether they will deliver on the environmental improvements promised.
From the program’s heady inception, the politicians got ahead of the science. Very little in the way of baseline nitrogen numbers for the region’s bays, harbors, and ponds was available. Testing has improved somewhat but it is still not clear how success will be measured. In almost all test sites, dissolved nitrogen has been below levels considered harmful by the Peconic Estuary Program. It is difficult to come up with a solution without understanding the problem first, but that is exactly what town and county officials have done in this case.
It has been a substantial gamble for property owners installing the low-nitrogen systems and for taxpayers to help pay for cash incentives designed to encourage more people to make the switch. These are not inexpensive. A mid-range system in East Hampton could cost about $20,000 before rebates. For that kind of money, the public should have demanded stronger assurances that they improve conditions in marine and aquatic habitats.
Even if the residential systems work to cut nitrogen flowing into groundwater, so far, they have been installed in a scattershot way too widely dispersed to target specific water quality problems. And despite a longstanding federal order, there remain many businesses here still relying on illegal outdated cesspools, which probably should have been a higher priority than forcing new technology on the public without clear, data-driven policy.
Cutting individual properties’ nitrogen flow may make homeowners and officials feel better, but it remains to be seen if the programs will really make things better for the environment.