Allen Parish, Louisiana
A shallow water table limits basements on 83% of Allen Parish's mapped land, a higher share than 90% of US counties. Shrink-swell clay limits houses without basements on 3%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 123 flood losses here since 2016, 0% of them in buildings with basements. 46% of homes were built before 1980, against 50% nationally; the median home dates from 1983.
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 Allen Parish
| Expansive clay (limits slab homes) | 3.5% |
| High water table (limits basements) | 82.8% |
| Septic fields very limited | 88.7% |
| Clay swell (LEP, by area) | 2.4% |
| High-swell land (LEP 6%+) | 3.5% |
| Mapped soil | 490,500 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Guyton | 22% | n/a |
| Caddo | 13% | n/a |
| Glenmora | 12% | n/a |
| Messer | 10% | n/a |
| Malbis | 5% | n/a |
| Beauregard | 5% | n/a |
How we count · survey areas LA003 (2025-09-03)
What the numbers mean here
On 83% of Allen Parish'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: 47.14 in, 12.61 in below the 1991-2020 average year of 59.75 in.
USDA rates 89% of the land very limited for septic absorption fields.
Drought
100% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 41 of the last 52 weeks; the most was 100% of its area, in 19 weeks, most recently on the October 13, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 100% |
| D2 severe or worse | 100% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
123 flood losses since 2016, $6.0 million paid. The worst year was 2020, with 55. Foundations of the buildings, where recorded: 81% slabs, 4% crawl spaces, 15% elevated. Median water depth outside the building: 11.5 in.
| Year | Flood losses |
|---|---|
| 2016 | 12 |
| 2017 | 15 |
| 2018 | 3 |
| 2019 | 13 |
| 2020 | 55 |
| 2021 | 1 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 24 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 59.75 in |
| 12 months to August 2026 | 47.14 in (-12.61) |
| 2025 | 53.09 in (-6.66) |
| Wettest year since 1895 | 1973: 85.49 in |
| Driest year since 1895 | 1924: 36.42 in |
| Days with 1 inch or more, normal at OBERLIN FIRE TWR (4 mi away) | 20.3 |
Homes
| Housing units | 9,587 |
| Median year built | 1983 |
| Built before 1980 | 46% |
| Built 2000 or later | 27% |
| Owner-occupied | 74% |
| Median value, owner-occupied | $104,500 |
| 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 |
|---|---|---|---|
| Evangeline Parish, LA | 25 mi | 26% | 79% |
| Jefferson Davis Parish, LA | 26 mi | 45% | 94% |
| Beauregard Parish, LA | 31 mi | 10% | 76% |
| Acadia Parish, LA | 35 mi | 21% | 97% |
| Vernon Parish, LA | 38 mi | 22% | 51% |
| Rapides Parish, LA | 41 mi | 31% | 52% |
| Calcasieu Parish, LA | 43 mi | 18% | 84% |
| St. Landry Parish, LA | 50 mi | 41% | 84% |
Sources: USDA SSURGO (September 3, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status