Alternative on-site wastewater treatment systems (OWTS) for nitrogen reduction are being investigated for use in Suffolk County, and while they may have utility in some cases, they are not a panacea to our individual wastewater treatment issues.
Here are some facts that one should consider before installing such a system.
Although alternative systems have been in use for more than a decade in some neighboring states, there is no data or study that shows subregional groundwater or surface water quality improvement. The best alternative OWTS are generally capable of reducing nitrogen by 50 percent as compared to a conventional sewage disposal system. In fact, the experience in other states indicates that 60 to 65 percent of the systems installed met their targeted nitrogen reductions. But this also means that 35 to 40 percent of the systems did not provide the required nitrogen reduction.
Alternative OWTS are complex treatment systems containing mechanical and electrical components that are not required for a conventional septic system. In order to ensure a functioning system, an operation and maintenance contract is a legally required necessity for the life of each OWTS installation. Because most systems require electric power, they are unable to treat wastewater during power interruptions as conventional gravity flow sewage systems can. Households connected to the public water supply continue to produce sewage during an electric outage. Requiring additional emergency storage in a septic tank, a gravity bypass or automatically activated standby power generation can mitigate the issue, but would add substantially to the system’s cost.
In addition, seasonal home occupancy can upset the system and reduce nitrogen treatment efficiency.
The cost of an alternative system is more than five times that of a conventional septic tank and leaching pools. The New Jersey Pinelands Commission reports that the cost for a typical alternative system averages $32,000. Suffolk County’s own study reported costs ranging from $25,000 to $41,000, as compared with the cost of a typical conventional sewage system in Suffolk County of $5,100. There are other costs associated with the program, as jurisdictions allowing alternative systems must have a bureaucracy for system tracking, monitoring and to ensure operation and maintenance contracts are in effect.
Property deed covenants must also be filed to ensure that future owners are aware of their responsibility to maintain the systems.
In late 1980s and early 1990s, Suffolk County had a program allowing alternative wastewater treatment systems for the purpose of allowing increased density at commercial properties. Nearly 400 such systems were installed, and virtually all failed. These properties received their density bonus of increased sewage flow, but none of these systems provided advanced nitrogen treatment. As Suffolk County again contemplates allowing alternative systems, perhaps they should be first installed at the sites of the first 400 failed systems, and their treatment efficiency closely monitored for several years, before their use is allowed elsewhere in the county.
Certainly, history has shown that no density bonus should be considered for installing an alternative system.
There is sufficient reason to proceed with caution when considering implementation of alternative on-site wastewater treatment systems based upon the costs, nearby states’ experience of inconsistent reliability, the lack of data to show improved water quality and their abysmal track record in Suffolk County.
Martin Trent has worked for the Suffolk County Department of Health Services as a chief public health sanitarian for 40 years and is now semi-retired. He lives in Orient.