Off-Grid Living in Tompkins County, New York

I'll be upfront: Tompkins County is one of those places where the answer to "can I do that off-grid?" depends heavily on which town you're standing in. There's no countywide zoning ordinance here. New York State law puts land-use authority in the hands of towns, villages, and cities, and Tompkins County's roughly nine towns and two villages (Ithaca, Caroline, Ulysses/Trumansburg, Lansing, and others) each run their own zoning code, usually posted on eCode360. So before you buy land or plan a build, find out which municipality it's in and pull that specific code.

That said, the County does step in for two big things: septic and wells, both handled by the Tompkins County Health Department (TCHD), Division of Environmental Health.

Zoning and dwelling types are entirely a town-by-town matter. I couldn't find a countywide position on tiny homes, RVs as dwellings, or minimum house size, because that's not how New York structures it, each town's zoning table decides what's permitted.

Building permits also run through local Code Enforcement Offices, not the county, but they're all enforcing the same New York State Uniform Fire Prevention and Building Code (established under Article 18 of the state Executive Law). So construction standards are statewide, but who reviews your plans and issues the permit is your town.

Septic is where the county actually has teeth. TCHD requires an OWTS (onsite wastewater treatment system) construction permit before you build new or do most repairs or replacements. Design has to follow the NYS Department of Health's Residential OWTS Design Handbook plus the Tompkins County Sanitary Code, and installation has to meet NYSCRR Appendix 75-A standards; fail inspection and you get a Non-Compliance Notification. I did not find a county rule specifically addressing composting toilets as a septic alternative, so ask TCHD directly.

Greywater and rainwater harvesting don't have dedicated Tompkins County pages that I could locate. That likely means you're working from the New York State baseline rules, which technically touch greywater through plumbing and health code but are notoriously hard to permit cleanly in practice. Rainwater collection for non-potable use is generally fine under the state baseline, but confirm nothing local overrides that.

Private wells are permitted countywide, with TCHD adding a documentation layer: your well driller's DEC well completion report has to be filed with the county, and water testing must go through a certified lab under Part 5 of the NYS Sanitary Code or the county's own Sanitary Code.

Living off-grid utility-wise (no grid electric, etc.) isn't addressed at the county level at all, it comes down to whether your specific town's zoning or building code requires a utility hookup for a permanent dwelling. Some towns are relaxed about this, some aren't, so this is a phone call worth making before you commit to land.