4. Constructing an addition to an existing home
An analysis of the existing wastewater system is required prior to any addition (see NYS DOH Fact Sheet). An addition could be reasonably defined as any modification to an existing structure which would likely increase the potential amount of wastewater generated in the structure. For most situations this would refer to an additional bedroom.

All aspects of NYS DOH Appendix 75-A must be adhered to for an addition. A waiver from the minimum requirements may only be granted by NYS DOH and only if detailed plans completed by a privately retained design professional have been submitted and approved by both the WPA and NYS DOH Hornell District Office. The WPA reserves the right to reject any plans submitted by a design professional.

The WPA has wastewater treatment system records for nearly all homes in Schuyler County, therefore an initial phone call should be made to the WPA as soon as possible in the planning stage for any home addition.

For all intents and purposes, the regulations for additions are identical with the regulations for new construction. The only difference being minimum lot size requirements need not be met. While the regulations may be similar, the existing infrastructure and useable area on a lot can certainly pose a challenge for upgrading a system and in some very rare cases, could negate the possibility for major home additions. For instance, the wastewater treatment system must maintain a minimum 100 ft separation distance to surface bodies of water, wells and all neighboring wells if this separation distance cannot be achieved as currently installed, mitigation measures must be sought.

The procedure for an addition is highly variable depending on several factors and will be determined at the discretion of the WPA based on the realities of the land and its infrastructure (wastewater system, well(s), lot size, surface water, etc) and the proposed changes.

An addition, at a minimum, will require a site evaluation with the applicant, an inspection of the septic tank during a mandatory tank pumping, excavation and inspection of drywell or distribution box, and requires a Compliance Certificate to be issued to the Town prior to issuing a Building Permit.

A majority of additions require more modifications and will require anything from a tank upgrade, to additional trench lines, to a whole new system, even a new well.