Oneida County, New York
A shallow water table limits basements on 53% of Oneida County's mapped land, a higher share than 69% of US counties. Shrink-swell clay limits houses without basements on under 1%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 306 flood losses here since 2016, 80% of them in buildings with basements. 75% of homes were built before 1980, against 50% nationally; the median home dates from 1958.
Data as of October 13, 2026 · sources
expansive clay: shrink-swell limits slab homes
high water table: limits basements
in drought, October 13, 2026
of homes built before 1980
Soil under Oneida County
| Expansive clay (limits slab homes) | 0.2% |
| High water table (limits basements) | 53.0% |
| Septic fields very limited | 75.1% |
| Clay swell (LEP, by area) | 1.8% |
| High-swell land (LEP 6%+) | 0.2% |
| Mapped soil | 805,900 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Adams | 5% | n/a |
| Kendaia | 5% | n/a |
| Worth | 4% | n/a |
| Lima | 3% | n/a |
| Alton | 3% | n/a |
| Honeoye | 3% | n/a |
How we count · survey areas NY065 (2025-09-04)
What the numbers mean here
On 53% of Oneida County's mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.
Rain over the 12 months to August 2026: 45.17 in, 2.38 in below the 1991-2020 average year of 47.55 in.
USDA rates 75% of the land very limited for septic absorption fields.
Drought
0% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 12 of the last 52 weeks; the most was 100% of its area, on the October 28, 2025 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
306 flood losses since 2016, $7.7 million paid. The worst year was 2017, with 134. Foundations of the buildings, where recorded: 80% basements, 12% slabs, 5% crawl spaces, 3% elevated. Median water depth outside the building: 18 in.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 134 |
| 2018 | 17 |
| 2019 | 125 |
| 2020 | 2 |
| 2021 | 10 |
| 2022 | 2 |
| 2023 | 8 |
| 2024 | 1 |
| 2025 | 5 |
| 2026 to date | 2 |
Rain
| Average year, 1991-2020 | 47.55 in |
| 12 months to August 2026 | 45.17 in (-2.38) |
| 2025 | 48.57 in (+1.02) |
| Wettest year since 1895 | 1972: 59.26 in |
| Driest year since 1895 | 1930: 35.16 in |
| Days with 1 inch or more, normal at BOONVILLE 4 SSW (14 mi away) | 12 |
Homes
| Housing units | 105,443 |
| Median year built | 1958 |
| Built before 1980 | 75% |
| Built 2000 or later | 10% |
| Owner-occupied | 68% |
| Median value, owner-occupied | $182,600 |
| Single-family detached | 63% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Madison County, NY | 26 mi | 2% | 57% |
| Lewis County, NY | 37 mi | under 1% | 50% |
| Herkimer County, NY | 37 mi | under 1% | 45% |
| Onondaga County, NY | 42 mi | 1% | 46% |
| Oswego County, NY | 42 mi | 1% | 59% |
| Otsego County, NY | 47 mi | 0% | 49% |
| Fulton County, NY | 52 mi | 0% | 47% |
| Chenango County, NY | 54 mi | 0% | 62% |
Sources: USDA SSURGO (September 4, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status