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Mendon, Ohio

Inside Mendon's city limits, a shallow water table limits basements on 98% of mapped land, the 5th-highest of 9 cities in Mercer County. Shrink-swell clay limits houses without basements on 16%.

That water-table share is close to Mercer County's 95%. FEMA's flood data list no flood losses since 2016 in ZIP code 45862 overlapping the city. Of its 260 homes, 93% were built before 1980; the median dates from 1949.

Data as of October 13, 2026 · sources · in Mercer County

16%

expansive clay: shrink-swell limits slab homes

98%

high water table: limits basements

0

flood losses since 2016 in 1 overlapping ZIP

93%

of homes built before 1980

Basement waterproofing in Mendon

Basement waterproofing in Mendon: a shallow water table limits basements on 98% of Mendon's mapped land, more than in 90% of Ohio cities.

About 200 of Mendon's 260 homes are detached houses.

Soil under Mendon city limits

Expansive clay (limits slab homes)15.8%
High water table (limits basements)97.9%
Septic fields very limited98.1%
Clay swell (LEP, by area)4.6%
High-swell land (LEP 6%+)0.7%
Mapped soil356 acres
Soil seriesShare hereSeries nationally: high water table
Blount53%over 99%
Pewamo15%99%
Saranac13%n/a
Glynwood7%over 99%
Spencerville5%n/a
Haskins2%n/a
Mercer CountyMendon
Mendon city limits inside Mercer County, shaded by the city's high water table share.under 10%10-25%25-40%40-60%60%+

How we count

What the numbers mean here

Clay swell averages a linear extensibility of 4.6% by land area here, and 1% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 16% of the mapped land.

On 98% of Mendon's mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.

USDA rates 98% of the land very limited for septic absorption fields.

Drought in Mercer County

0% of Mercer County is in drought (D1 or worse) on the October 13, 2026 map. County detail.

October 21, 2025Share of area in drought, weeklyOctober 13, 2026

Flood losses by ZIP code

FEMA flood records since 2016 in the ZIP codes that overlap Mendon. ZIP areas reach past city limits.

ZIPShare of city landFlood lossesPaid
45862100%0$0

Homes in Mendon

Housing units260
Median year built1949
Built before 198093%
Built 2000 or later2%
Owner-occupied85%
Median value, owner-occupied$100,000
Single-family detached94%

Nearby cities

PlaceDistanceExpansive clayHigh water table
Elgin 5 mi 69% over 99%
Rockford 7 mi 27% 98%
Venedocia 8 mi 29% 100%
Celina 8 mi 23% 67%
Ohio City 9 mi 65% over 99%
Spencerville 9 mi 29% 99%
St. Marys 11 mi 11% 68%
Montezuma 13 mi 24% 92%

Sources: USDA SSURGO (August 5, 2026) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · Census ACS 2020-2024. Methods · Data status