Quick Answer:
If you get brown water right after finishing a repair at a single fixture, the most likely cause is loose solder flux, pipe debris, or dislodged rust from the repair work. Don’t panic — shut the fixture off, capture and flush the line, and recheck before using the water for drinking or cooking.
Why This Happens
- Repairs disturb sediment, rust, and solder residue inside pipes. Those particles can travel to the fixture and color the first few gallons of water.
- Solder flux, small metal filings, or scale from old pipes often shows up as brown, tea-colored, or slightly metallic-looking water.
- Work on a branch line can dislodge rust that moves into the fixture but not into the whole house plumbing — that’s why it’s often limited to the repaired fixture.
- Similar causes appear in other scenarios, such as after a long idle period or when aerators collect loose particles — see examples like Water turns brown after long vacation and Rust flakes in sink aerator for related issues.
Step-by-Step What to Do
1. Stop using the fixture and shut it off if needed
Close the faucet and, if you left it partially open during the repair, fully shut the supply valve feeding that fixture. This avoids pulling more debris into the tap while you prepare to flush and inspect.
2. Prepare to catch flushed water
- Place a clean bucket or large container under the supply connection or the fixture to collect the first discharge. You don’t want discolored water going down the drain or into your water heater.
- Have rags and gloves on hand — flushed water can look unpleasant and may contain particles.
3. Remove and flush the supply line
Remove the supply line at the repaired fixture and flush into a bucket to catch leftover debris. Open the valve slowly and allow the line to run until the water clears. If you used a flexible braided line, inspect the end for filings or solder residue.
4. Check the aerator and fixture parts
- Unscrew the aerator or spray head and inspect for brown particles or rust flakes. Clean or replace the aerator screen before reattaching.
- Look inside the faucet and supply fittings for visible debris. Wipe parts clean and reassemble only after the water runs clear.
5. Flush the fixture and nearby lines
With the supply line reattached, turn the water on at full flow for several minutes. Check both hot and cold sides separately; hot-water lines can carry sediment from the heater. If discoloration clears, run the water a bit longer to be sure.
6. Verify whole-house water if needed
If brown water appears at multiple taps or returns quickly after flushing, the issue may be farther back in the system (main, water heater, or corroded pipe). At that point, follow the When to Call a Professional section below.
What Not to Do
- Do not drink from the repaired line until debris is fully purged.
- Don’t assume the problem has gone away after only a few seconds of flushing — flush until the water is clear and particle-free.
- Do not use strong acids or unknown chemicals to clear the line yourself — that can damage plumbing and the water supply.
- Avoid reheating or re-soldering a joint that still looks contaminated; clean and flush first, then rework if necessary.
When to Call a Professional
- If brown water persists at the repaired fixture after thorough line flushing and aerator cleaning.
- If multiple fixtures show discoloration or if the water has an unusual odor or metallic taste.
- If you see continuous large particles, active corrosion, or a damaged valve that you can’t safely repair yourself.
- If the problem involves the water heater or main supply line — those require specialist tools and experience.
Safety Notes
- Wear gloves and eye protection when working with open fittings and flushing lines. Small particles can splash.
- Dispose of flushed water safely — collect it in a bucket and pour it into a utility sink or outdoor area that can handle discoloration.
- If soldering was involved, ensure joints are fully cooled before touching and that flux residue is wiped away to prevent contamination.
- Shut off the main water supply if you can’t stop a leak or if debris continues to flow uncontrollably.
Common Homeowner Questions
- Why is the water brown only at that one faucet? Small repairs often dislodge local rust or debris that sits in that branch of piping; it doesn’t always reach the rest of the house.
- How long should I flush before the water is safe? Flush several minutes and until the water runs clear; if it takes more than 5–10 minutes or returns, get help.
- Can I fix this without a plumber? Yes, if the cause is local debris: removing the supply line, flushing into a bucket, and cleaning the aerator usually works. Call a professional if discoloration persists or multiple fixtures are affected.
For more related articles, see the Brown or Rust-Colored Water Events hub.