Last updated: October 2026

You should test your well water after flooding if floodwater reached or covered the wellhead, if the well cap was damaged, or if your water changes color, smell or taste after heavy rain. Floodwater can carry bacteria and other contaminants into a well through a loose cap, cracked casing or poor grading. Until the water tests clean, use bottled water for drinking and cooking. A flooded well usually needs disinfection followed by a bacteria test to confirm it's safe.

Two large water storage tanks on a rural property beside a wire fence

How Does Floodwater Get Into a Well?

Through the top. A cracked or loose well cap, casing that ends too close to the ground, or soil that slopes toward the well lets surface water run in. Low spots where water pools around the wellhead are the biggest risk.

What Are the Signs Your Well Was Affected?

  • Water was standing over or around the wellhead.
  • Muddy, cloudy or discolored water.
  • New odors or tastes.
  • Equipment in the well house got wet.

Even if the water looks clear, bacteria can't be seen. Testing is the only way to know.

What Should You Do After a Flood?

  1. Stop drinking the water; use bottled water.
  2. Don't turn the pump on if the well house or electrical equipment was underwater — call a professional first.
  3. Have the well inspected for damage to the cap, casing and wiring.
  4. Disinfect the well (shock chlorination) if needed.
  5. Test for bacteria afterward to confirm the water is safe.

The Texas Well Owner Network and the TCEQ's private well guidance both cover well owner responsibilities after flooding.

How Do You Prevent It Next Time?

Make sure the well has a sealed, intact cap, the casing extends above ground, and soil slopes away from the wellhead. Our well inspections check all three.

Frequently Asked Questions

How long after flooding should I test?

Test after the well has been inspected and disinfected, then follow up to confirm results.

Will a filter make flooded well water safe?

Not on its own. Disinfection comes first. Some homes add ongoing treatment like UV — see our bacteria treatment page.

Do you do water testing?

Yes. See well water testing.

Worried about your water after the rain? Call 817-374-2548 or get your free quote — no obligation.