On Site Sewage Disposal

What is a "Realty Subdivision"?

A realty subdivision is a development of 5 or more lots that are being developed for residential purposes. The Nassau County Department of Health has delegated authority from the State Department of Health and the Department of Environmental Conservation to approve plans for the water supply, sewage disposal and drainage aspects of these developments before construction may begin.

I am building a home or renovating my home. Do I need to submit engineering plans to the Health Department for a new septic system?

Not necessarily. The Health Department has jurisdiction over septic systems for developments (realty subdivisions) of 5 lots or more. If your home is not part of a new realty subdivision or if you are renovating your existing home,  you should contact your local building department for any septic system approval requirements.

I am starting a new restaurant or expanding an existing restaurant in a non-sewered area. Do I need to submit engineering plans to the Health Department for the septic system?

If the site does not have an existing septic system, plans must be submitted to the Health Department for review and approval prior to its installation. If a septic system exists, it must be evaluated by a licensed professional engineer as to whether it is adequate to handle the new or added flow. This evaluation must be reviewed by the Department and a determination will be made whether the system needs to be modified or expanded and plans need to be submitted. In addition, a permit must be obtained from the Bureau of Environmental Sanitation - Office of Food Protection.

Does my commercial establishment in a non-sewered area require engineering plans?

Yes. If a commercial establishment has a design flow of greater than 1000 gallons per day, then a plan submittal is required to the Health Department and a New York State Department of Conservation - State Pollutant Discharge Elimination System (SPDES) permit is required.

Do you have any guidelines to design a septic system?

Yes. The Department has a "Manual of On Site Sewage Disposal". A copy can be obtained by calling (516) 227-9672.

Is there a fee for submitting engineering plans?

Yes. Please call (516) 227-9672 for the schedule of fees.

How can I obtain more information?

You may call the Department at (516) 227-9672 for more information.