Environmental groups on the East End have recently been responsible for a concerted effort to push municipalities on the upgrading of existing sanitary systems. One recent letter to The Suffolk Times included some phrases that have been used lately by people regarding pollution in our creeks, such as “under-performing septic systems” and “upgrading our sanitary systems.”
I have lived in Southold since 1974 and I am as concerned about the quality of our surface waters as the environmental groups. That letter asks the reader to “push the Town Board into action,” but just what action is it asking the Town Board to take with our sanitary systems?
The majority of the sanitary systems on the North Fork are on-site subsurface wastewater disposal. These typical home systems require a one-time installation expense, as well as periodic pumping. These subsurface systems, even when compliant with Suffolk County requirements, do not remove nitrates from the effluent.
We also have one sewage treatment plant in town, in Greenport, that services the specific area of Greenport Village.
I do not know the definition of “under-performing,” but if all on-site home sanitary systems are to be upgraded, we must assume that they will be upgraded to current Suffolk County Health Department standards. As an engineer, I am intimately knowledgeable of the steps required for a sanitary system upgrade and the costs involved.
The following are only some of what the process involves.
• Surveys to locate all details of the property and system.
• Test boring to evaluate soil conditions and depth to groundwater.
• Engineering inspection and design fees.
• Construction to remove and replace existing sanitary system.
• Landscaping costs for bringing a property back to its original condition.
The cost to the homeowner for upgrading a substandard, “underperforming” sanitary system for a 3- to 4-bedroom home would be in the range of $10,000 to $18,000. That does not include a concrete retaining wall, if required by grading.
Even if all homeowners close to surface waters made this sanitary upgrade, there is no proof that this would solve any surface water problems. Existing sub-surface sanitary systems that are compliant with Suffolk County Health Department requirements do not remove nitrates. They may become more efficient in removing other contaminants but any upgrade will not remove nitrates.
Another option being considered is small-package sewage treatment plants used in communities adjacent to surface waters. These plants would be denitrification plants. Let’s look at the costs for these small cluster sanitary systems.
I live in the older community of Founder’s Estates, which we can use as an example. This is a community of about 150 quarter- and half-acre lots adjacent to Town Creek. If we use the standard of 300 gallons per day for a sanitary flow we get 45,000 gallons per day needed for the size of the sewage treatment plant. If we could find a place to put the package sewage treatment, construction costs for the plant would be $8.25 million. The cost for each homeowner in Founder’s Estates would be $55,000. The annual operating cost for homeowners would be about $1,600, which would be added to each homeowner’s tax bill every year.
There are experimental package plants that remove nitrogen and are about 1/3 less costly to build; however, these experimental sanitary systems have not been approved by any municipality at the present time. There is a very good report regarding sanitary system costs — “Understanding the Cost Factors of Wastewater Treatment and Disposal” — that was prepared this year by the Cape Cod Commission in Massachusetts. Cape Cod is very much like the East End of Long Island in its topography and soil conditions. The costs noted in that report are in line with what I have noted here. There may be solutions to the problems of surface water pollution. Some technology is not here yet and we may need to wait for that to come. It is important that the financial burden to the citizens of the town is considered when evaluating requirements to upgrade existing sanitary systems.
Joseph Fischetti is a licensed professional engineer of 40 years and is board certified in structural engineering. He runs a private practice in Southold providing civil and structural engineering.