Drought and Your Foundation: What OKC Homeowners Should Do Now

Oklahoma County is in severe drought right now

As of October 20, 2026, the US Drought Monitor shows 100% of Oklahoma County in severe drought (category D2) or worse, with 2.39% in extreme drought (D3). D2 is not a casual label: it marks dryness in roughly the driest 5 to 10 percent of historical conditions.

If you have noticed a new crack in the drywall, a door that suddenly sticks, or a gap where the baseboard meets the floor, the weather is a likely suspect. The good news is that drought movement is common, well understood, and often manageable when you catch it early.

If you already see something that worries you, a quick photo is an easy first step.

Why Oklahoma City clay moves

Much of the metro sits on clay soils that swell when they get wet and shrink when they dry. Soil scientists measure this with linear extensibility percent (LEP): how much a soil's length changes between moist and oven-dry. The USDA Natural Resources Conservation Service (NRCS) rates shrink-swell potential as low below 3%, moderate from 3 to 6%, high from 6 to 9%, and very high above 9%. NRCS notes that moderate to very high ratings can damage buildings and roads.

The main culprits around OKC are the Kirkland, Renthin and Renfrow soil series. The NRCS official description of Kirkland, for example, lists 35 to 40 percent clay in the subsoil and "slickensides," shiny polished surfaces that form when clay repeatedly swells and slides against itself. That is the soil literally recording years of movement.

A house slab rests on top of all this. When the soil under one part of the house shrinks more than the soil under another part, the slab and the framing above it flex. That uneven movement, called differential movement, is what cracks walls and racks door frames.

The wet-dry cycle

Clay does not just shrink once. It shrinks in dry spells and swells back after soaking rains, over and over. Each swing nudges the structure a little. Long droughts followed by heavy rain are the hardest on a house, because the change is bigger and faster.

Why cracks show up in late summer and fall

Soil moisture usually bottoms out after months of summer heat. By late summer and early fall, the clay around and under the edges of your slab has lost the most water, so the perimeter can drop slightly relative to the middle of the house. That is when many homeowners first notice new cracks, gaps over doors, or windows that will not latch.

Here is the part that confuses people: some of those cracks partly close after a good rain. The clay swells back, the slab edge rises a bit, and the gap narrows. That does not mean the problem went away. A crack that opens and closes with the seasons is a sign that the soil under your home is cycling, and it is worth tracking.

• Mark the ends of a crack with a pencil and write the date next to it.
• Take a photo with a coin or ruler for scale.
• Check again every few weeks, and after big rains.

Not sure which signs matter? Our guide to signs of foundation problems walks through them, or you can run through a short checklist.

2026 compared with past droughts

We counted, for each year since 2000, the number of weeks when at least half of Oklahoma County was in severe drought or worse. The chart below shows that history.

Weeks per year with at least half of Oklahoma County in severe drought (D2 or worse)

The takeaway: 2026 has already logged 34 such weeks, the most since 2011 (39 weeks) and 2006 (41 weeks), and more than 2022 (32 weeks). Homes that came through those earlier droughts are now going through another long one.

How trees and lawn watering affect your foundation

Trees pull water out of the ground through their roots, and in a drought there is less of it to go around. A large tree close to one corner of the house can dry the clay on that side faster than the rest, which is a recipe for uneven settling.

Lawn watering cuts both ways. A sprinkler zone that soaks the front yard while the back stays bone dry creates exactly the uneven moisture you want to avoid. So does a downspout that dumps water in one spot. The goal is even, steady moisture all the way around, not more water in some places.

• Keep gutters clean and downspouts extended away from the house.
• Make sure soil slopes away from the slab so rain does not pond against it.
• If a big tree sits close to the house, ask a certified arborist about root management before cutting anything. Cutting large roots can harm the tree or make it unstable.

How to water your foundation (a practical how-to)

Foundation watering means keeping the soil next to your slab from drying out and pulling away. Done well, it reduces how far the clay shrinks. Done badly, it can make things worse by soaking one spot. Here is a sensible approach, drawn from guidance by a Texas A&M AgriLife Extension water resources specialist working with the same kind of expansive clay found in central Oklahoma.

1. Use a soaker hose or drip line, not a sprinkler. Lay it in the soil or bed about 8 to 18 inches out from the foundation, all the way around the house. Do not lay it against the slab, where water can run straight down along the concrete.
2. Water in several short cycles instead of one long soak. Clay takes water in slowly, so short cycles let it soak in rather than run off.
3. Mulch the beds. A 2 to 4 inch layer of mulch slows evaporation and keeps the soil temperature down.
4. Aim for consistency. The target is soil that stays evenly moist, not muddy. Push a long screwdriver into the soil near the slab: if it goes in easily, you are doing enough. If water pools, cut back.
5. Water early in the day to lose less to evaporation, and check your city's current watering rules before setting a schedule.
6. Watch the gap. If the soil has pulled away from the slab and left an open crack, water gently and let it close gradually. Avoid flooding the gap.

Watering is most useful on high shrink-swell soils. If your home sits on sandy soil, it matters much less.

Which OKC ZIP codes sit on the most expansive soils?

We mapped NRCS soil survey data across 63 residential ZIP codes in the metro. Shrink-swell risk varies a lot from one side of town to the other.

ZIP	Area	Average LEP	Land on high shrink-swell soil
73159	South Oklahoma City	7.55%	84%
73139	South Oklahoma City	6.93%	79%
73120	Northwest OKC, The Village	6.70%	75%
73162	Northwest Oklahoma City	6.49%	73%
73119	Southwest Oklahoma City	6.68%	69%
73160	Moore	5.89%	66%

On the east side, the picture flips. Choctaw (73020, LEP 2.07%), Midwest City (73130, 2.09%), Harrah (73045, 2.13%) and east Edmond (73034, 2.32%) sit mostly on sandier Stephenville and Harrah soils with low shrink-swell potential. Homes there can still have foundation problems, but drought is less often the main driver.

See where your street falls on our foundation risk map, or look up your ZIP directly.

When watering is not enough

Watering helps prevent further shrinkage. It does not lift a slab that has already settled or fix a cracked foundation. Call for an inspection if you see any of these:

• Cracks that are wide enough to catch a fingernail, or that keep growing between checks
• Stair-step cracks in brick, or brick pulling away from window frames
• Floors that slope enough to notice when you walk
• Doors or windows that stick in several rooms, not just one
• Gaps between walls and the ceiling or floor

A local foundation specialist can measure how level your slab is, check whether movement is ongoing, and tell you whether watering and drainage fixes are enough or whether repairs such as piers (steel or concrete supports driven down to firmer soil) make sense. For a sense of what repairs run, see our foundation repair cost guide.

If any of those signs sound familiar, an on-site look is the clearest next step.

The short version

Severe drought plus Oklahoma City clay is a known combination, and 2026 has the longest run of severe drought in Oklahoma County since 2011. Keep the soil around your home evenly moist with a soaker hose set back from the slab, fix drainage, keep an eye on big trees, and track any cracks with dates and photos. If cracks grow or doors start sticking around the house, have the foundation checked before the next wet season swings things back the other way.