Quick Answer:
If you turn on a tap after being away and the water is brown, it is usually stagnant water mixed with rust or sediment. Don’t panic. Start by running water to clear the lines: open the lowest faucet in the home first to dump stagnant water, then move upward floor by floor. If the discoloration clears quickly you likely do not have a major leak or contamination problem.
Why This Happens
- Water left sitting in pipes or the water heater can pick up rust, sediment and minerals that discolor the flow.
- Older galvanized or iron pipes can corrode inside; short periods of stagnation let loosened rust enter the water.
- Municipal work, pressure changes or a flushed main can temporarily disturb iron and sediment in the supply lines.
- If only hot water is brown, sediment in the water heater is often the source.
Step-by-Step What to Do
1. Start at the lowest point
Open the lowest faucet in the home first to dump stagnant water, then move upward floor by floor. This pushes the older water out from the bottom and prevents it from migrating back down as you work.
2. Run cold water until clear
At each fixture, run the cold tap for several minutes or until the water clears. Cold water is the best first check because it comes directly from the supply line and not from the heater.
3. Check the hot water separately
After the cold water is clear, run the hot tap. If the hot side is brown but the cold side is clear, the water heater likely has sediment. Avoid heavy use of hot water until you confirm it is clear.
4. Flush toilets and appliances
- Flush each toilet once or twice to clear bowls and tanks.
- Run a short rinse cycle on the dishwasher and washing machine only after faucets are clear to avoid staining clothing or dishes.
5. Compare with neighbors and outdoor taps
Try an outdoor spigot or ask a neighbor if they see brown water. If others report the same issue, contact your water provider — the problem may be in the distribution system.
6. If discoloration persists
If brown water remains after clearing each fixture for several minutes, note where it appears (hot vs cold, upstairs vs downstairs) and move to the next step: consider contacting a plumber or the water utility for testing and inspection.
What Not to Do
- Do not drink or cook with discolored water until it clears or you know it is safe.
- Do not run large laundry loads or wash delicate whites until the water is clear — stains are possible.
- Do not leave stagnant water sitting in the heater after vacations.
- Do not attempt major repairs if you are unsure—call a professional rather than risking damage to plumbing components.
When to Call a Professional
- If brown water does not clear after you run multiple fixtures for several minutes.
- If the brown water has a metallic or fuel-like smell, or if anyone in the home experiences illness after using the water.
- If you see signs of pipe corrosion, leaks, or a sudden drop in water pressure.
- If the hot water is consistently discolored even after flushing the heater — a plumber can inspect and flush the heater or recommend replacement.
Safety Notes
- Do not use discolored water for drinking, cooking, or brushing teeth until it clears or has been tested.
- Avoid using hot water for bathing or laundry until you confirm the hot supply is clear, to reduce risk of staining and minimize contact with sediment.
- If you suspect contamination beyond rust (unusual odor, cloudiness, or illness), contact your water utility for testing and follow their guidance.
Common Homeowner Questions
- Is it safe to drink the water?
Not until it clears or is tested. Use bottled water or an alternative source for drinking and cooking if the water is visibly discolored. - Will this stain my clothes?
Yes, brown or rusty water can stain fabrics. Wait until water runs clear before doing laundry. - How long should I run the taps?
Run until the water is clear; this may take a few minutes at each fixture. Start at the lowest point and work upward for best results.
Rusty water from bathtub only and Brown water from upstairs faucets only are common variations; use the steps above to isolate whether the issue is local to one fixture, the water heater, or the whole home.
For more related articles, see the Brown or Rust-Colored Water Events hub.