Drought, Watering and Concrete on North Texas Clay

Clay and moisture

The dark clay common in North Richland Hills and the Mid-Cities is highly expansive. When it absorbs water, it swells; when it dries, it shrinks and cracks. Driveways, patios and walkways sit on top of that soil and move with it.

Movement on its own is manageable if it's even. Problems start when one part of a slab sits on wet, swollen clay and another part on dry, shrunken clay. That uneven support causes cracks, tilting and settlement.

So the goal isn't to stop all moisture changes, which is impossible, but to keep them as even as possible around and under the slab.

Sprinklers and watering days

North Richland Hills limits outdoor watering to twice a week year-round. On watering days, sprinkler heads that spray onto driveways and walks soak the soil along one edge while the rest stays drier.

Adjusting heads so they water the lawn and beds, not the concrete, helps keep moisture more even. Drip irrigation in beds next to slabs is another option.

During droughts, moderate and even watering of beds and lawn near slabs, within the city's rules, can reduce shrinkage at slab edges.

Trees and maintenance

Large trees draw lots of water from the soil, especially in summer, drying the clay near them more than elsewhere. Walks and driveways near big trees often crack or settle in a line toward the trunk.

Sealing cracks and joints keeps water from reaching the base unevenly. Checking slabs after storms and droughts helps catch settling early, when leveling is easier.

If panels have tilted, sunk or created trip edges, leveling or partial replacement can restore them before the damage spreads.

When planting new trees, keeping larger species well away from driveways and walks reduces future problems. A tree that will grow large is best planted at a distance from slabs at least equal to its expected spread.