Monroe County, New York
A shallow water table limits basements on 55% of Monroe County's mapped land, a higher share than 71% of US counties. Shrink-swell clay limits houses without basements on 6%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 200 flood losses here since 2016, 44% of them in buildings with basements. 70% of homes were built before 1980, against 50% nationally; the median home dates from 1965.
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 Monroe County
| Expansive clay (limits slab homes) | 6.2% |
| High water table (limits basements) | 54.9% |
| Septic fields very limited | 68.9% |
| Clay swell (LEP, by area) | 2.7% |
| High-swell land (LEP 6%+) | 6.2% |
| Urban land, not rated | 5.4% |
| Mapped soil | 426,577 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Hilton | 9% | n/a |
| Ontario | 9% | n/a |
| Collamer | 5% | n/a |
| Appleton | 3% | n/a |
| Niagara | 3% | n/a |
| Colonie | 3% | n/a |
How we count · survey areas NY055 (2025-08-27)
What the numbers mean here
On 55% of Monroe 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: 40.34 in, 5.72 in above the 1991-2020 average year of 34.62 in.
USDA rates 69% 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 21 of the last 52 weeks; the most was 100% of its area, in 15 weeks, most recently on the January 27, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 25% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
200 flood losses since 2016, $1.9 million paid. The worst year was 2017, with 119. Foundations of the buildings, where recorded: 44% basements, 13% slabs, 31% crawl spaces, 12% elevated. Median water depth outside the building: 7 in.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 119 |
| 2018 | 5 |
| 2019 | 37 |
| 2020 | 2 |
| 2021 | 9 |
| 2022 | 2 |
| 2023 | 5 |
| 2024 | 1 |
| 2025 | 9 |
| 2026 to date | 11 |
Rain
| Average year, 1991-2020 | 34.62 in |
| 12 months to August 2026 | 40.34 in (+5.72) |
| 2025 | 30.97 in (-3.65) |
| Wettest year since 1895 | 2017: 45.05 in |
| Driest year since 1895 | 1934: 23.48 in |
| Days with 1 inch or more, normal at ROCHESTER GTR INTL AP (9 mi away) | 5.1 |
Homes
| Housing units | 339,430 |
| Median year built | 1965 |
| Built before 1980 | 70% |
| Built 2000 or later | 12% |
| Owner-occupied | 64% |
| Median value, owner-occupied | $213,700 |
| Single-family detached | 62% |
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 |
|---|---|---|---|
| Orleans County, NY | 26 mi | 5% | 77% |
| Genesee County, NY | 30 mi | 4% | 63% |
| Wayne County, NY | 33 mi | 1% | 56% |
| Ontario County, NY | 34 mi | 11% | 59% |
| Livingston County, NY | 36 mi | 24% | 78% |
| Wyoming County, NY | 46 mi | 0% | 72% |
| Yates County, NY | 52 mi | 1% | 83% |
| Seneca County, NY | 55 mi | 11% | 57% |
Sources: USDA SSURGO (August 27, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status