Duval County, Florida
A shallow water table limits basements on 78% of Duval County's mapped land, a higher share than 87% 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, after 64.7% a week earlier. FEMA's flood data list 3,091 flood losses here since 2016, 2% of them in buildings with basements. 40% of homes were built before 1980, against 50% nationally; the median home dates from 1986.
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 Duval County
| Expansive clay (limits slab homes) | 6.1% |
| High water table (limits basements) | 78.1% |
| Septic fields very limited | 81.3% |
| Clay swell (LEP, by area) | 1.7% |
| High-swell land (LEP 6%+) | 6.3% |
| Urban land, not rated | 8.2% |
| Mapped soil | 544,500 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Leon | 14% | n/a |
| Pelham | 9% | 100% |
| Boulogne | 7% | n/a |
| Tisonia | 6% | n/a |
| Surrency | 6% | n/a |
| Mascotte | 5% | n/a |
How we count · survey areas FL031 (2025-08-28)
What the numbers mean here
On 78% of Duval 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: 35.48 in, 15.55 in below the 1991-2020 average year of 51.03 in.
USDA rates 81% 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 51 of the last 52 weeks; the most was 100% of its area, in 36 weeks, most recently on the September 1, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 69.1% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
3,091 flood losses since 2016, $176.3 million paid. The worst year was 2017, with 2,050. Foundations of the buildings, where recorded: 2% basements, 71% slabs, 17% crawl spaces, 10% elevated. Median water depth outside the building: 15 in.
| Year | Flood losses |
|---|---|
| 2016 | 546 |
| 2017 | 2,050 |
| 2018 | 24 |
| 2019 | 16 |
| 2020 | 34 |
| 2021 | 31 |
| 2022 | 265 |
| 2023 | 21 |
| 2024 | 94 |
| 2025 | 7 |
| 2026 to date | 3 |
Rain
| Average year, 1991-2020 | 51.03 in |
| 12 months to August 2026 | 35.48 in (-15.55) |
| 2025 | 44.76 in (-6.27) |
| Wettest year since 1895 | 1991: 71.83 in |
| Driest year since 1895 | 1990: 29.35 in |
| Days with 1 inch or more, normal at JACKSONVILLE NAS (7 mi away) | 13.7 |
Homes
| Housing units | 454,740 |
| Median year built | 1986 |
| Built before 1980 | 40% |
| Built 2000 or later | 32% |
| Owner-occupied | 58% |
| Median value, owner-occupied | $303,500 |
| Single-family detached | 59% |
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 |
|---|---|---|---|
| Nassau County, FL | 20 mi | 7% | 93% |
| Clay County, FL | 27 mi | under 1% | 68% |
| St. Johns County, FL | 35 mi | 5% | 88% |
| Baker County, FL | 39 mi | 0% | 99% |
| Camden County, GA | 40 mi | 23% | 92% |
| Bradford County, FL | 41 mi | 0% | 93% |
| Charlton County, GA | 41 mi | 1% | 99% |
| Union County, FL | 47 mi | 0% | 94% |
Sources: USDA SSURGO (August 28, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status