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After the Flood: Is Your Water Safe to Drink?

After a flood, drinking water sources may be contaminated - be safe before you drink the water.

Regardless of whether you have your own water supply, get water from a public water system (PWS), or operate a public water system, you might have to take special steps to ensure that your drinking water is safe after the well or water treatment plant has been flooded. 

These links will take you to information that can help you ensure that your water supply is safe: 

Much of this information is in PDF format. (Help with PDF.)

Steps for PWSs to Recover from Low Water Pressure

If your drinking water distribution system has lost operating pressure, be sure to follow these steps, as outlined in the special precautions  flowchart  found in the rules for public drinking water systems: 

  1. Notify your customers immediately to boil water they use in cooking, for drinking, or for making ice. Be sure to issue the boil-water notice in both English and Spanish.
  2. Notify the TCEQ regional office that serves your county.
  3. Take the measures needed to flush your distribution system, disinfect it, and ensure its integrity.
  4. Take representative samples to ensure that clean water is available in all parts of your system. To have your water samples analyzed, see our list of labs accredited to test drinking water.
  5. Once you have confirmed that your distribution system is producing a stable supply of clean water (through acceptable results for Steps 3 and)  you may lift the boil-water notice. Notify your customers and the TCEQ. 

The complete rules for public water systems are found in Title 30, Texas Administrative Code, Chapter 290. Two subchapters of these rules are available for reference: 

  • Rules and Regulations for Public Water Systems: Subchapter D  
  • Drinking Water Standards Governing Drinking Water Quality & Reporting Requirements for Public Water Systems: Subchapter F  

If you have other questions, contact either our regional office or the Water Supply Division in our central office (512/239-4691) for guidance. 

Advice for customers of PWSs

To disinfect water by boiling, bring it to a full boil, continue to boil for two minutes, and then let the water cool before using it. For more information see   After a Disaster: Is your Drinking Water Safe? and the EPA’s Web page on the emergency disinfection of drinking water   . 

If you have not been told to boil your water, ask yourself these questions: 

  1. Did my home flood? If yes, see "Flooding on Your Property." 
  2. Did the flood cover any part of the water line between my water meter and my house? If yes, see "Flooding on Your Property." 
  3. When I opened a faucet, did an unusually weak stream of water or no water come out? If yes, see Reporting a Water Outage. 

Flooding on Your Property

If your home or any part of your property above your water lines was flooded, it would be a good precaution to flush your service line and household plumbing as follows: 

  • Starting with the outside faucet farthest from your meter, run water through the faucet until you notice a change in water temperature. Then shut the faucet off. 
  • Working back towards the water meter, continue flushing one faucet or water fixture at a time. Remove the aerator before you flush kitchen or bathroom faucets. At each faucet, this flushing procedure should take five minutes or less. 
  • Be sure to drain and refill your water heater also. 

Flushing should remove any air or contaminants that may have entered your plumbing system when the service was interrupted. 

Reporting a Water Outage

If your faucet produces no water or only a weak stream and you have not already been told to boil your water, call your water system immediately to report a possible outage in your neighborhood. 

Then boil or disinfect your water  . 

Be alert for water leaks and outages after a flood, too. If the flood washed soil away from a water main, the water main could break days or weeks later. Report leaking mains or outages to your water system immediately. 

Advice for disinfecting your own well

If your well has been flooded, disinfect your well and have a water sample analyzed by a laboratory certified to test drinking water.