Septic Systems in New York

62 counties · ~22% of homes on septic · ~627,058 septic systems

State Regulation Overview

Regulatory Body
New York State DEC
Inspection Required for Sale
No / Varies by county
Nitrogen Reduction Areas
Yes
Advanced Treatment Areas
Yes

Suffolk County and Long Island have strict nitrogen rules. County health departments issue permits.

Top Counties by Septic Systems

Kings County
~36,116 septic homes
Queens County
~31,752 septic homes
Erie County
~25,192 septic homes
New York County
~22,364 septic homes
Richmond County
~21,813 septic homes

All Counties in New York

Albany County
315K pop · ~11% septic
Allegany County
46K pop · ~26.4% septic
Bronx County
1473K pop · ~3.3% septic
Broome County
199K pop · ~16.5% septic
Cattaraugus County
77K pop · ~22% septic
Cayuga County
76K pop · ~22% septic
Chautauqua County
128K pop · ~16.5% septic
Chemung County
84K pop · ~22% septic
Chenango County
47K pop · ~26.4% septic
Clinton County
80K pop · ~22% septic
Columbia County
62K pop · ~22% septic
Cortland County
47K pop · ~26.4% septic
Delaware County
44K pop · ~26.4% septic
Dutchess County
296K pop · ~16.5% septic
Erie County
954K pop · ~6.6% septic
Essex County
37K pop · ~26.4% septic
Franklin County
48K pop · ~26.4% septic
Fulton County
53K pop · ~22% septic
Genesee County
58K pop · ~22% septic
Greene County
48K pop · ~26.4% septic
Hamilton County
5K pop · ~30.8% septic
Herkimer County
60K pop · ~22% septic
Jefferson County
117K pop · ~16.5% septic
Kings County
2736K pop · ~3.3% septic
Lewis County
27K pop · ~26.4% septic
Livingston County
62K pop · ~22% septic
Madison County
68K pop · ~22% septic
Monroe County
759K pop · ~6.6% septic
Montgomery County
50K pop · ~26.4% septic
Nassau County
1396K pop · ~3.3% septic
New York County
1694K pop · ~3.3% septic
Niagara County
213K pop · ~16.5% septic
Oneida County
232K pop · ~16.5% septic
Onondaga County
477K pop · ~11% septic
Ontario County
112K pop · ~16.5% septic
Orange County
401K pop · ~11% septic
Orleans County
40K pop · ~26.4% septic
Oswego County
118K pop · ~16.5% septic
Otsego County
59K pop · ~22% septic
Putnam County
98K pop · ~22% septic
Queens County
2405K pop · ~3.3% septic
Rensselaer County
161K pop · ~16.5% septic
Richmond County
496K pop · ~11% septic
Rockland County
338K pop · ~11% septic
Saratoga County
236K pop · ~16.5% septic
Schenectady County
158K pop · ~16.5% septic
Schoharie County
30K pop · ~26.4% septic
Schuyler County
18K pop · ~26.4% septic
Seneca County
34K pop · ~26.4% septic
St. Lawrence County
109K pop · ~16.5% septic
Steuben County
94K pop · ~22% septic
Suffolk County
1526K pop · ~3.3% septic
Sullivan County
79K pop · ~22% septic
Tioga County
48K pop · ~26.4% septic
Tompkins County
106K pop · ~16.5% septic
Ulster County
182K pop · ~16.5% septic
Warren County
66K pop · ~22% septic
Washington County
61K pop · ~22% septic
Wayne County
91K pop · ~22% septic
Westchester County
1004K pop · ~3.3% septic
Wyoming County
41K pop · ~26.4% septic
Yates County
25K pop · ~26.4% septic

Septic Systems in New York

Approximately 22% of homes in New York rely on septic systems for wastewater treatment, totaling an estimated 627,058 septic systems across the state's 62 counties. This places New York among the states with significant decentralized wastewater infrastructure.

Septic Regulations in New York

Septic regulations in New York are administered by New York State DEC, with permits typically issued at the county level through local health departments. Requirements for tank sizes, setback distances, approved system types, and inspections can vary significantly between counties.

While New York does not have a statewide mandate for septic inspections at the time of property sale, individual counties may impose their own requirements. It is common practice for buyers to request a septic inspection as part of their due diligence, even when not legally required.

Common Septic System Types

Homeowners in New York typically use one of several septic system types depending on local soil conditions: conventional gravity-fed systems where soil percolation is adequate, pressure distribution systems in areas with moderate limitations, mound systems where shallow bedrock or high water tables prevent conventional installation, and aerobic treatment units (ATUs) in environmentally sensitive areas or nitrogen reduction zones.

Septic Maintenance Requirements

The EPA recommends pumping septic tanks every 3 to 5 years, though the exact frequency depends on tank size, household size, and water usage. In New York, some counties have adopted mandatory pumping schedules or maintenance tracking programs. Proper maintenance prevents costly repairs, protects groundwater quality, and extends the lifespan of the drainfield — the most expensive component to replace.

Select a county above to view detailed septic regulations, estimated costs, soil suitability data sourced from the USDA NRCS Soil Survey, and groundwater depth measurements from the USGS.

Data last updated: 2026-04-13