Buying a Home With a Septic System in Northern Westchester or Putnam
Updated 2026-10-06
Most homes for sale in Northern Westchester and Putnam County are not on public sewer. If you are buying one, the septic system is one of the biggest unknowns in the house, and one of the most expensive to replace. Here is what to check before you close.
1. Confirm the house is actually on septic
Parts of Yorktown, Mount Kisco and other towns are sewered and parts are not, sometimes street by street. Ask the seller, check the tax bill for a sewer charge, and confirm with the town. Don't assume either way.
2. Pull the county records
In Westchester, the county Department of Health keeps approved septic and well records, called sketches, for many properties. Anyone can request them. The request needs the address, the original tax map designation, the municipality, the year the house was built and the dates of any additions. Records in the archives can take up to 10 business days, so ask early (Westchester County DOH).
The sketch shows where the tank and drain field are supposed to be and how many bedrooms the system was approved for. If the house has more bedrooms now than the system was designed for, that is a red flag worth raising with your attorney.
In Putnam County, ask the town building department and the Putnam County Department of Health what records exist for the property.
3. Check the pumping history
Westchester requires septic tanks to be pumped at least every five years, and pumpers report each pump-out to the county. Ask the seller for receipts. A system that has not been pumped in years may already be pushing solids into the drain field. In Putnam, pumping rules are set town by town, so ask the seller whether they have kept up with the local schedule.
4. Get a real septic inspection
A general home inspection usually does not cover the septic system in depth. A proper septic inspection typically includes:
- Locating the tank and drain field and comparing them to the county sketch
- Pumping the tank, so the inspector can see the walls, baffles and outlet
- Checking the drain field for saturation, odor or surfacing water
- Noting the tank material and age. Old steel tanks rust out.
- A written report with photos
Get the report in writing before your contingency deadline. If it finds problems, you have room to negotiate a repair, a credit or a price change.
5. Know the local rules that affect repairs
Much of this area sits in the New York City watershed, which adds rules for how septic systems are designed, repaired and replaced. In Putnam County, septic repairs must be done by a county-licensed contractor unless the owner does the work. Properties near Lake Oscawana in Putnam Valley fall under extra requirements because the lake is listed as impaired. Repairs in these areas can take longer and cost more than buyers expect.
6. Ask about help with replacement costs
New York State runs a septic system replacement fund for select locations in Putnam County, and income-qualified residents may be eligible for loans or financial assistance through the Putnam County Housing Corporation at 845-225-8493 (Putnam County DOH). In Westchester, homeowners who pay county sewer tax but use septic may qualify for maintenance reimbursement.
Quick checklist
- Confirm septic or sewer with the town
- Request the county septic records early
- Get pump-out receipts from the seller
- Book a septic inspection that includes pumping
- Compare approved bedrooms to actual bedrooms
- Read the report before your contingency expires
Need an inspection?
We connect buyers and sellers across Northern Westchester and Putnam County with independent, county-licensed septic companies. Call or request a quote and mention it's for a home sale.
Sources: Westchester County Department of Health, Putnam County Department of Health.