Quick Answer:
If multiple faucet aerators fill with grit overnight while the water looks normal, it often means a fresh release of sediment upstream. Immediately unscrew the aerators and photograph the debris, flush each affected line without screens, then watch the fixtures. If debris returns quickly, treat as an entry-side issue and protect appliances while investigating.
Why This Happens
Even when water looks clear, small particles can move through the system and collect where flow slows, like aerators. Common causes include recent work on the water main, hydrant flushing, pressure changes that dislodge sediment, corrosion inside pipes, or a failing tank-style water heater. Movement of grit can also cause other problems you may notice later, such as Pressure loss due to sediment buildup or parts that no longer seat cleanly.
Step-by-Step What to Do
1. Gather a few simple items
- Small adjustable pliers or aerator key
- Soft cloth or towel
- Phone or camera to photograph debris
- Container to catch debris or run it to a drain
2. Unscrew the aerators and photograph the debris
- Turn off knobs, use a cloth to protect finishes, and remove aerator inserts carefully.
- Place removed parts on a towel and take clear close-up photos of any grit or particles. Keep these photos for your records and to show your water utility or plumber.
3. Inspect the debris briefly
- Note color, particle size, and whether particles look metallic, sandy, or organic. That helps you and a pro narrow the source.
4. Flush each affected line without screens
- With the aerator off, run the cold tap at full force for 1–2 minutes to clear loose material. Do this for each affected faucet separately.
- Catch what comes out or let it run to a drain so particles don’t end up in appliance inlets.
5. Recheck and monitor
- After flushing, reinstall a clean aerator (or leave it off temporarily) and watch the water for several minutes to an hour.
- If debris returns quickly, treat this as an entry-side issue and protect appliances while investigating.
- If debris does not return, continue to monitor for the next day — occasional small slugs can pass without further action.
6. Protect appliances while you investigate
- Shut off water supply valves to sensitive appliances (dishwasher, washing machine, refrigerator ice maker) or install a temporary coarse filter on their inlet hoses.
- Do not run cycles until you are confident the grit is gone to avoid damage to valves and pumps.
What Not to Do
- Don’t keep reinstalling aerators without flushing upstream; you’ll just trap more grit.
- Don’t assume a single clogged aerator is an isolated problem when multiple fixtures show the same grit.
- Don’t try to clear a municipal main break yourself — contact the water utility if you suspect a main issue.
When to Call a Professional
Call a licensed plumber or your water utility if any of the following apply:
- The debris returns quickly after flushing and shows up at multiple fixtures.
- Particles look metallic or you notice smells, discoloration, or unexplained pressure changes.
- Appliances or valves start acting up — for example, if you suspect Debris causing valves to leak or if a valve no longer shuts completely.
- You cannot isolate the source or you spot signs of ongoing pipe damage.
Safety Notes
- Wear gloves when handling debris and aerator parts.
- Avoid using hot water to clear debris first — hot water can circulate particles into the heater or appliances before you notice them.
- If you suspect contamination (odd color, odor, or health risk), avoid drinking the tap water and use bottled water until the issue is resolved.
- If work has been done on a municipal main, check with your water utility before doing any in-home repairs related to the main.
Common Homeowner Questions
- Why did this happen overnight? A pressure change or recent upstream work can dislodge sediment quickly, sending it downstream during low-use periods.
- Will a screen on the aerator fix it? A screen may catch grit temporarily, but without flushing upstream the screen just traps more debris and can hide a bigger problem.
- Can I keep using the water? Short-term use for washing is usually fine after flushing, but avoid drinking or running appliances until you’re sure grit is gone.