Check the current local notice
Contact the water supplier, local authority or emergency service and ask whether a boil-water, do-not-drink or do-not-use notice applies to your area and source. Follow the exact instructions, including when the notice is lifted.
If floodwater entered a rooftop tank, well, bore, pipe opening or household storage container, tell the authority. Keep people away from electrical equipment and unsafe roofs or tank openings while the area is being checked.
Use a different source when contamination is uncertain
If authorities say the water is unsafe, use an alternative source that they identify as suitable for drinking, food preparation and brushing teeth. Do not use visibly contaminated floodwater or water that may contain sewage, fuel or industrial chemicals.
Boiling and chemical disinfection do not remove fuel or toxic chemicals. If those may be present, do not try to fix the water with a household filter, tablets or boiling; ask the local authority what source to use.
Treat only as the advisory directs
A boil-water notice and a chemical contamination warning require different responses. If the notice calls for boiling or another treatment, follow the stated method and storage instructions. Do not substitute a different treatment without approval.
If there is no clear notice but the supply has changed after a break, contact the supplier rather than guessing how long to flush the tap or whether a household filter is enough. Advice can depend on the repair and the water system.
After service returns
Follow the supplier's directions for flushing household plumbing, cleaning or disinfecting tanks, and restarting filters or other treatment equipment. Do not enter a tank yourself; use qualified help where needed.
If water remains discoloured, smells unusual, or the authority recommends testing, pause use for drinking and food preparation and contact a qualified laboratory. Keep a note of the incident, the affected source and any test report.
Frequently asked questions
Can boiling make floodwater safe to drink?
Do not assume so. Boiling can address some microbial risks when authorities advise it, but it does not remove fuel or toxic chemicals. Follow local instructions and use another source if chemical contamination is possible.
Can I drink tap water as soon as a broken pipe is repaired?
Not automatically. Check with the water supplier for any advisory and its instructions for your specific repair and supply.
What if floodwater entered my rooftop tank?
Do not rely on the tank until the local authority or a qualified provider tells you how to inspect, clean, disinfect and, if needed, test the system. Do not enter the tank yourself.