Water Debris Contamination (not from well?) FAQs

Diagnose Debris in Water Supply when it's Not from the Well

Came home to an empty water tank and bits of black debris in our water

We have a well. We went on 10 day vacation. When we came home, the water tank was completely empty. We don't know how long it was like this. Got it up and running after replacing several pieces.

Since then, the tank has emptied out 1 time. It has been 21 days and there is still black rubber like pieces (not rust) in our water.

All water (baths, sinks, washer). Can't drink or cook with it now. Even dog gets bottled water now.

Do you think the bladder in the tank dried up and is disintegrating? We share a well with the other half of our house so we know its not a problem with the well itself. On 2017-08-19 by Keri

by (mod) - First look for a leaky check valve or foot valve

Keri,

Cause of the Empty Water Tank

The fact that you had an empty water tank and no water after being away for ten days is a strong suggestion of a check valve or foot valve leak in your well piping system.

This problem happens most-often when there is a bad foot valve or check valve on the water system between pump/tank and well, and when power is off for a time. When power is on, even though water leaks back into the well, the pressure drop turns on the pump and it keeps its prime and keeps water in the tank.

But if power is off for a while water runs back into the well and the tank is emptied, the pump loses prime and IF it's not a submersible unit it'll have to be re-primed. In contrast, a submersible pump will simply run again when power is restored.

Possible sources of debris in the water

The most common sources of black debris or sediment in water originate at the water source (mud, soil, organic debris, minerals, often from a damaged well casing) but I agree that it's possible for these to be coming from your water piping, valves, or more-likely a damaged pump impeller.

Debris particles in a building water supply might come from any one of several common sources I'll list below:

1. Damaged water pump or tank parts - which can occur if the pump ran "dry" for a time

   A bad bladder in the pressure tank might give rubber debris but so can damage in the pump, pump gaskets, or well piping, depending on what materials were used. But a "dried up" tank bladder ought to show up as a well pump short cycling as you've lost the benefit of the pressure tank on the line.
   
   The fact that you describe the particles as black and rubber-like suggests damage to the pump impeller, less likely the tank bladder or to other plastic parts.

2. Low water in the well - your well pump or foot valve may be picking up dirt sand debris - a condition more common in well sunk in sandy silty or clay soils.
3. Damaged foot valve screen or well screen at the water pick-up at the bottom of your well piping can pick up silt and debris, especially if the pick-up is too close to the bottom of the well bore.
4. Damaged well casing - allowing dirt to fall into the well where it's picked up by the well pump or foot valve (that dirt can also clog or jam a foot valve that could explain the empty water tank I discussed above.
5. Damaged well cap or top seal - can allow dirt or other debris into the well, more-likely if the well top is below ground or in a flood-prone well pit.
6. Damaged or contaminated local water treatment equipment - for example see WATER SOFTENER OUTPUT COLORS DEBRIS STAINS ODORS 
7. Rusted or corroded iron water pipes - is your water piping galvanized iron? How old is it? Is the water supply corrosive? Rust in water pipes or in an older steel water tank can show up as debris particles in the water supply.
   

More diagnostic questions for debris in the water supply:

The fact that your home is duplexed and uses a common well doesn't tell me clearly how the system is set-up.

Are you using a common pump too, perhaps a submersible in the well? If so why would you have a separate water pressure tank from the other building occupants?

Do you see the black junk in both hot and cold water?

Do you see debris at every plumbing fixture or only certain ones? (Remember to try removing screens on faucets and removing shower heads to clean out the debris).

Do the neighbors see the black junk in their water?

Do both homes use water sediment or debris filters?

These references on well water contaminants including sediment and particulates may be helpful

• US EPA, Potential Well Water Contaminants and their Impacts (EPA Website) U.S. Environmental Protection Agency - local backup copy saved as Well-Water-Contaminants-EPA.pdf
• NDSU, Protecting Your Water Source: What’s the Condition of Your Water Well? [PDF] (AE1951, Revised June 2025) North Dakota State University, - local backup copy saved as Protecting-Water-Source-NDSU.pdf

Repair advice:

1. Answer the diagnostic questions I raised above
2. Check the pump impeller for damage
3. Collect debris samples and have them examined by a forensic microscopic lab (don't send them to me; though I have done much forensic microscopy I've retried from that work)
4. Collect a water sample for examination and test by a local water test laboratory

Let me know what you find and we can proceed from there. Daniel Friedman