Quick Answer:
If you see particles only from upstairs taps and showers, the problem is usually local to the fixtures, aerators, or the supply branch that serves the upper floor — not guaranteed internal collapse of a vertical riser. Start by comparing upstairs and downstairs cold taps side by side, check aerators and showerheads, and isolate which fixtures are affected before assuming the riser is corroded.
Why This Happens
- Mineral deposits, rubber washer fragments, or bits from a failing fixture can look like grit coming from the tap.
- Debris can collect in aerators or showerhead screens and then wash out when flow changes. If you see dark particles from a showerhead, those are often rubber bits, residue, or mineral flakes — see Black specks from showerhead for more detail.
- Work on the municipal system (valve switching or hydrant flushing) can dislodge sediment that enters only one branch of your home supply. That situation can produce patterns similar to what homeowners report in Black flecks after city shutoff.
- Some supply lines or fittings to the upstairs branch can deteriorate or shed material without the main riser being visibly corroded. But you need simple checks first to know where the particles originate.
Step-by-Step What to Do
1. Do a quick side-by-side comparison
Run the cold tap upstairs and the cold tap downstairs at the same time and observe both flows. This simple side-by-side check shows whether the issue is only on the upstairs branch or present throughout the house.
2. Check cold vs hot
Run cold and hot separately at the upstairs fixture. If particles appear only on cold, the problem is likely in the cold supply to that floor (fixture, aerator, or branch). If only hot, the water heater or a hot branch may be involved.
3. Inspect and clean aerators and showerheads
- Shut the faucet off, unscrew the aerator or remove the showerhead screen and look for trapped debris.
- Rinse parts in a cup of clear water and watch for particles to appear. This often removes the cause without further work.
4. Test nearby fixtures
Try other fixtures on the same floor (bathroom sink, another shower, utility sink). If multiple fixtures on the upstairs branch show particles, the problem is likely in the branch or a shared fitting rather than a single fixture.
5. Isolate using accessible shutoffs
- If your upstairs fixtures have individual shutoff valves under sinks or near toilets, close them to see if particles stop when the fixture is isolated.
- If closing a fixture’s isolation valve stops particles at that fixture but others still show them, you’ve localized the issue to that fixture or its short supply run.
6. Collect a sample and document
Catch water in a clear glass to let particles settle, take a photo, and note whether particles float, sink, or discolor the water. These details help a plumber diagnose the source.
7. If you suspect the riser, don’t assume worst-case yet
If all upstairs fixtures show particles even after cleaning aerators and isolating individual fixtures, you may have a problem in the upstairs branch or riser. At that point, call a professional to inspect accessible valves and the riser from accessible points rather than opening walls.
What Not to Do
- Do not open walls before isolating riser involvement. Removing drywall is invasive and unnecessary until you know the particles truly come from behind the wall.
- Do not ignore dark or metallic-looking particles — document and stop using the water for drinking until you know what they are.
- Do not use strong chemical cleaners inside supply lines or fixtures without guidance from a plumber; that can damage seals or create health risks.
When to Call a Professional
- If particles persist after cleaning aerators and isolating fixtures.
- If you see metallic flakes, brown or orange discoloration, or detect a metallic taste — these can indicate pipe corrosion or mineral issues that need testing.
- If particles appear suddenly after city work, or if you cannot find a local source and the problem affects multiple upstairs fixtures.
Safety Notes
- Avoid drinking or cooking with water that contains unknown particles until you know what they are.
- Wear gloves when handling dirty aerators or collected samples. Some particles can be sharp or contaminated.
- If you suspect lead or other hazardous material, limit household use and call a qualified plumber or certified testing service for samples and testing.
Common Homeowner Questions
- Why are particles only upstairs? The upstairs branch, fixtures, or fittings may be shedding material or holding sediment separate from the downstairs supply.
- Can this wait until next week? If particles are minor and only cosmetic, you can start with cleaning aerators. If they’re dark, metallic, or affect drinking water, act sooner and avoid using the water for consumption.
- Will flushing the pipes fix it? Flushing can remove loose sediment, but it won’t fix a failing fitting or corroded pipe; use flushing as a diagnostic step and follow up if the problem returns.
For more related articles, see the Black Specks, Sediment, or Grit in Water hub.