Scott County, Iowa
A shallow water table limits basements on 41% of Scott County's mapped land, a higher share than 59% of US counties. Shrink-swell clay limits houses without basements on 36%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 268 flood losses here since 2016, 37% of them in buildings with basements. 63% of homes were built before 1980, against 50% nationally; the median home dates from 1972.
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 Scott County
| Expansive clay (limits slab homes) | 36.1% |
| High water table (limits basements) | 40.8% |
| Septic fields very limited | 90.4% |
| Clay swell (LEP, by area) | 4.4% |
| High-swell land (LEP 6%+) | 3.2% |
| Urban land, not rated | 3.7% |
| Mapped soil | 299,900 acres |
How we count · survey areas IA163 (2025-09-09)
What the numbers mean here
Clay swell averages a linear extensibility of 4.4% by land area here, and 3% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 36% of the mapped land.
On 41% of Scott 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: 34.13 in, 3.59 in below the 1991-2020 average year of 37.72 in.
USDA rates 90% 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 18 of the last 52 weeks; the most was 100% of its area, in 5 weeks, most recently on the March 31, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 0% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
268 flood losses since 2016, $9.4 million paid. The worst year was 2019, with 144. Foundations of the buildings, where recorded: 37% basements, 22% slabs, 3% crawl spaces, 38% elevated. Median water depth outside the building: 28 in.
| Year | Flood losses |
|---|---|
| 2016 | 8 |
| 2017 | 5 |
| 2018 | 19 |
| 2019 | 144 |
| 2020 | 3 |
| 2021 | 2 |
| 2022 | 0 |
| 2023 | 45 |
| 2024 | 24 |
| 2025 | 16 |
| 2026 to date | 2 |
Rain
| Average year, 1991-2020 | 37.72 in |
| 12 months to August 2026 | 34.13 in (-3.59) |
| 2025 | 33.60 in (-4.12) |
| Wettest year since 1895 | 2009: 50.16 in |
| Driest year since 1895 | 2005: 19.83 in |
| Days with 1 inch or more, normal at ROCK ISLAND L&D 15 (9 mi away) | 10.1 |
Homes
| Housing units | 78,537 |
| Median year built | 1972 |
| Built before 1980 | 63% |
| Built 2000 or later | 21% |
| Owner-occupied | 70% |
| Median value, owner-occupied | $222,000 |
| 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 |
|---|---|---|---|
| Rock Island County, IL | 12 mi | 6% | 32% |
| Clinton County, IA | 18 mi | 15% | 44% |
| Cedar County, IA | 28 mi | 39% | 43% |
| Muscatine County, IA | 28 mi | 20% | 50% |
| Mercer County, IL | 31 mi | 15% | 44% |
| Henry County, IL | 32 mi | 19% | 48% |
| Jackson County, IA | 36 mi | 1% | 18% |
| Whiteside County, IL | 37 mi | 2% | 40% |
Sources: USDA SSURGO (September 9, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status