Oswego County, New York
A shallow water table limits basements on 59% of Oswego County's mapped land, a higher share than 73% of US counties. Shrink-swell clay limits houses without basements on 1%.
66.6% of the county is in drought on the October 13, 2026 Drought Monitor map, up from 0% a week earlier. FEMA's flood data list 52 flood losses here since 2016, 31% of them in buildings with basements. 61% of homes were built before 1980, against 50% nationally; the median home dates from 1971.
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 Oswego County
| Expansive clay (limits slab homes) | 0.8% |
| High water table (limits basements) | 59.2% |
| Septic fields very limited | 76.3% |
| Clay swell (LEP, by area) | 1.6% |
| High-swell land (LEP 6%+) | 0.8% |
| Mapped soil | 651,800 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Worth | 11% | n/a |
| Empeyville | 8% | n/a |
| Ira | 7% | n/a |
| Scriba | 6% | n/a |
| Hinckley | 4% | n/a |
| Colton | 4% | n/a |
How we count · survey areas NY075 (2025-09-04)
What the numbers mean here
On 59% of Oswego 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: 47.32 in, 1.33 in above the 1991-2020 average year of 45.99 in.
USDA rates 76% of the land very limited for septic absorption fields.
Drought
66.6% 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 | 66.6% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
52 flood losses since 2016, $773,471 paid. The worst year was 2019, with 17. Foundations of the buildings, where recorded: 31% basements, 10% slabs, 38% crawl spaces, 21% elevated. Median water depth outside the building: 10 in.
| Year | Flood losses |
|---|---|
| 2016 | 2 |
| 2017 | 17 |
| 2018 | 8 |
| 2019 | 17 |
| 2020 | 3 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 3 |
| 2024 | 2 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 45.99 in |
| 12 months to August 2026 | 47.32 in (+1.33) |
| 2025 | 46.12 in (+0.13) |
| Wettest year since 1895 | 1976: 55.43 in |
| Driest year since 1895 | 1934: 32.11 in |
| Days with 1 inch or more, normal at OSWEGO (16 mi away) | 6.4 |
Homes
| Housing units | 54,844 |
| Median year built | 1971 |
| Built before 1980 | 61% |
| Built 2000 or later | 13% |
| Owner-occupied | 73% |
| Median value, owner-occupied | $151,700 |
| Single-family detached | 68% |
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 |
|---|---|---|---|
| Onondaga County, NY | 31 mi | 1% | 46% |
| Cayuga County, NY | 36 mi | 3% | 56% |
| Jefferson County, NY | 38 mi | 15% | 47% |
| Oneida County, NY | 42 mi | under 1% | 53% |
| Lewis County, NY | 44 mi | under 1% | 50% |
| Wayne County, NY | 45 mi | 1% | 56% |
| Madison County, NY | 47 mi | 2% | 57% |
| Seneca County, NY | 56 mi | 11% | 57% |
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