Coconino County, Arizona
USDA's soil survey flags shrink-swell clay on 15% of Coconino County's mapped land and a shallow water table under basements on 1%, both below the national shares of 15% and 29%. The soil survey maps 75% of the county's land area; these shares describe the mapped part.
48.1% of the county is in drought on the October 13, 2026 Drought Monitor map, down from 51.1% a week earlier. FEMA's flood data list 99 flood losses here since 2016, 4% of them in buildings with basements. 28% of homes were built before 1980, against 50% nationally; the median home dates from 1991.
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 Coconino County
| Expansive clay (limits slab homes) | 14.9% |
| High water table (limits basements) | 0.8% |
| Septic fields very limited | 62.4% |
| Clay swell (LEP, by area) | 3.6% |
| High-swell land (LEP 6%+) | 19.0% |
| Mapped soil | 8,915,926 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Winona | 7% | n/a |
| Sheppard | 4% | n/a |
| Mespun | 2% | n/a |
| Deama | 2% | n/a |
| Epikom | 2% | n/a |
| Monue | 2% | n/a |
How we count · survey areas AZ625 (2025-08-26), AZ629 (2025-08-26), AZ631 (2025-08-26), AZ639 (2025-08-25), AZ641 (2025-08-26), AZ643 (2025-08-28), AZ693 (2025-08-27), AZ699 (2025-08-27), AZ701 (2025-08-27), AZ707 (2025-08-27), AZ711 (2025-08-27), AZ714 (2025-08-27), UT689 (2025-08-28)
What the numbers mean here
Rain over the 12 months to August 2026: 12.01 in, 0.74 in below the 1991-2020 average year of 12.75 in.
USDA rates 62% of the land very limited for septic absorption fields.
With shrink-swell clay on 15% and a shallow water table on 1% of the land, the soil survey points to neither problem across most of Coconino County; conditions still vary lot by lot.
Drought
48.1% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 52 of the last 52 weeks; the most was 100% of its area, in 18 weeks, most recently on the August 18, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 48.1% |
| D2 severe or worse | 22.1% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
99 flood losses since 2016, $2.0 million paid. The worst year was 2022, with 36. Foundations of the buildings, where recorded: 4% basements, 71% slabs, 14% crawl spaces, 11% elevated. Median water depth outside the building: 8 in.
| Year | Flood losses |
|---|---|
| 2016 | 4 |
| 2017 | 3 |
| 2018 | 1 |
| 2019 | 8 |
| 2020 | 4 |
| 2021 | 30 |
| 2022 | 36 |
| 2023 | 12 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 1 |
Rain
| Average year, 1991-2020 | 12.75 in |
| 12 months to August 2026 | 12.01 in (-0.74) |
| 2025 | 10.57 in (-2.18) |
| Wettest year since 1895 | 1905: 23.87 in |
| Driest year since 1895 | 2020: 5.63 in |
| Days with 1 inch or more, normal at PHANTOM RCH (26 mi away) | 0.9 |
Homes
| Housing units | 70,645 |
| Median year built | 1991 |
| Built before 1980 | 28% |
| Built 2000 or later | 31% |
| Owner-occupied | 60% |
| Median value, owner-occupied | $448,000 |
| 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 |
|---|---|---|---|
| Navajo County, AZ | 87 mi | 7% | under 1% |
| Yavapai County, AZ | 93 mi | 29% | under 1% |
| Kane County, UT | 100 mi | 4% | under 1% |
| Mohave County, AZ | 111 mi | 6% | under 1% |
| Apache County, AZ | 132 mi | 7% | 2% |
| Washington County, UT | 137 mi | 4% | 1% |
| Garfield County, UT | 139 mi | 4% | 1% |
| Gila County, AZ | 151 mi | 30% | under 1% |
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