Well Water After a Flood, Hurricane, Wildfire or Earthquake
Short answer: after a flood, hurricane, wildfire or earthquake, don't drink your well water until it has been checked and tested. At minimum test for bacteria (total coliform and E. coli). After a wildfire, also ask a certified lab about volatile organic compounds (VOCs). Find a lab on your state page or province page.
Well water after flooding or a hurricane
If floodwater or hurricane storm surge covered your wellhead, the CDC and EPA say to treat the water as contaminated: use bottled water or boil it, disinfect the well (shock chlorination), then test. The CDC says to wait at least 7 to 10 days after disinfecting, so the chlorine is flushed out, before you test for total coliform and E. coli or fecal coliform. It recommends follow-up tests in the next 2 to 4 weeks and again in 3 to 4 months. More detail: testing water after flooding and flood season testing.
Well water after a wildfire
Health Canada says not to use your well water if a fire or wildfire happened close to your well or property: it can be contaminated by fire suppressants, ash and chemicals from melted well parts. The CDC and Health Canada say to test for VOCs and semi-volatile organic compounds (SVOCs) at a certified lab if there was a lot of fire damage, the well lost pressure, well parts were damaged, or parts are plastic (PVC, HDPE) or rubber. The CDC also suggests considering metals such as lead, copper, zinc and iron. Ask the lab how to sample, because some health departments ask you to let water sit still for a set time before a VOC sample.
Well water after an earthquake
The Alaska Department of Environmental Conservation says shaking can stir up sediment and make well water cloudy or discolored, which often clears in hours or days. Use another water source until it clears, inspect the well for damage, flush at a low flow, then disinfect and test for total coliform bacteria. Alaska DEC also suggests nitrate, and arsenic where it occurs naturally. If cloudiness lasts or the well's flow changes, call a well contractor.
What to test after any disaster
- Always: total coliform and E. coli (bacteria).
- Near farms or septic systems: nitrate.
- After wildfire damage: VOCs and SVOCs, plus metals if your lab or health department suggests them.
- If the water changed color or taste: see well water problems by symptom.
Use a lab your state or province certifies for the test you need. Many county health departments help after disasters.
Sources
- CDC: How to disinfect wells after an emergency
- EPA: What to do with your private well after a flood
- CDC: Private wells after a wildfire
- Health Canada: Well safety during and after emergencies
- Alaska DEC: Earthquake recovery for homeowners
Questions
When should I test well water after a flood?
CDC says to wait at least 7 to 10 days after disinfecting, then test for total coliform and E. coli, with follow-up tests in 2 to 4 weeks and 3 to 4 months.
What should I test after a wildfire?
Bacteria at minimum; CDC and Health Canada say to test for VOCs and SVOCs if there was heavy fire damage, pressure loss, or plastic well parts.
Why is my well water cloudy after an earthquake?
Shaking can stir up sediment; Alaska DEC says it often clears in hours or days. Flush, disinfect and test for bacteria.
Free well water safety checklist
15 family-friendly steps based on CDC and EPA guidance. Print it, keep it on the fridge, and know when to call a certified lab.
More guides
- How Much Does Well Water Testing Cost? Real Lab PricesReal published prices from public labs, free programs, and the EPA-approved-lab myth.
- Testing Tap, Spring, Lake, River or Pond WaterTap, spring, lake, river and pond water: where to test, and why pools and aquariums are different.
- Well Water Smells, Looks or Tastes Bad? Problems by SymptomSulfur smell, brown or cloudy water, black specks, bad taste: what each can mean and what to test.
- Flood Protection for Well Owners: Before, During and After a FloodRaise and seal the wellhead, know your pump shutoff, then disinfect and test with a certified lab after any flood.