More than 23 million American households drink from a private well, around 43 million people in all, and most of them assume someone is checking it. Nobody is.
That is not a scare story, it is simply how the rules are drawn. Municipal supplies are tested constantly and reported publicly. A private well is the owner’s responsibility from the water table to the tap.
Is Well Water Safe to Drink?
Well water is safe to drink when it is tested and the results are clean, and unsafe when it is not, which sounds obvious until you notice that nothing about the water tells you which. Bacteria and nitrates are invisible and tasteless. Private wells are not regulated under the Safe Drinking Water Act, and the EPA places that responsibility on the well owner.
Key Takeaways
- Private wells are not covered by federal drinking water rules.
- Test annually for coliform bacteria, nitrates, pH and dissolved solids.
- The dangerous contaminants are the ones you cannot see or taste.
- Retest after flooding or any work on the well, not just on schedule.
- Sudden changes in color, smell or grit are worth acting on immediately.
What to Test For, and When
| Test | How often | Why |
|---|---|---|
| Coliform bacteria | Yearly | Indicates surface water reaching the well |
| Nitrate | Yearly, more with an infant | Serious for babies, common near farmland |
| pH and dissolved solids | Yearly | Affects corrosion and taste |
| Arsenic, radon, uranium | Once, then per local advice | Geological, varies by region |
| Anything, after a flood | Immediately | Flooding contaminates wells routinely |
The last row is the one people skip. Floodwater carries surface contamination straight into a wellhead, and the water can look completely normal afterward. Test before drinking it again, and shock chlorinate if bacteria show up.
When the Water Changes
Rotten egg smell
Hydrogen sulfide, from sulfur bacteria or from the aquifer itself. If the smell appears only on the hot tap, suspect the water heater anode rod rather than the well.
Brown, red or black water
Iron gives brown or red, manganese gives black staining. Neither is usually a health emergency, but a sudden change after years of clear water can mean the well is drawing from a disturbed level.
Sand or grit
This one is a pump problem as much as a water problem. Sand means the screen or casing is passing solids, and every hour of it wears the pump’s clearances away. It is the fastest route to a failed pump, and the symptoms are covered in our guide to telling whether a well pump is bad.
Cloudy water
Usually air or fine sediment. Air in the line often means the water level has dropped near the pump intake, which is worth checking before it turns into a dry-run failure.
What the Pump Has to Do With It
A pump does not clean water, but it decides what the water picks up on the way. A unit set too close to the well bottom draws sediment that a properly positioned one would not, which is why installation depth matters as much for water quality as for pump life.
Running a well hard enough to draw the level down also pulls from parts of the aquifer that were not contributing before, and that can change water chemistry. Sizing to the well’s actual yield, as covered in our guide to sizing a submersible well pump, avoids both problems.
Practical steps for protecting a wellhead, keeping contamination out at the surface and maintaining the casing are set out in the EPA’s guidance on protecting your home’s water.
Keeping a Well Sound
- Keep the wellhead above grade and capped, so surface water cannot enter.
- Slope the ground away from the casing.
- Keep chemicals, fuel and manure well clear of the wellhead.
- Have the well inspected when you service the pump, since the access is already open.
- Keep the test results. A run of years shows trends a single test cannot.
The seasonal service routine that keeps the pump side sound is in our guide to maintaining a well pump.
Frequently Asked Questions
Can well water make you sick?
Yes, well water can make you sick when it carries coliform bacteria, E. coli or nitrates, none of which change how the water looks or tastes. That is the reason testing matters more on a well than on a municipal supply. Nitrate is the most serious for infants, because high levels interfere with how a baby’s blood carries oxygen.
How often should you test well water?
Test well water once a year for coliform bacteria, nitrates, pH and total dissolved solids. Test again outside that schedule after flooding, after any work on the well, if a septic system nearby has trouble, or if the taste, smell or appearance changes. Households with an infant or a pregnancy should test nitrates more often.
Why does well water smell like rotten eggs?
Well water smells like rotten eggs because of hydrogen sulfide, produced either by sulfur bacteria in the well or by chemistry in the aquifer. One quick test tells you a lot: if the smell is only on the hot tap, the water heater anode rod is the likely source rather than the well itself.
Why is my well water brown?
Brown or reddish well water is nearly always iron, while black staining points to manganese and cloudy water usually means sediment or air. Sudden brown water after years of clear is worth investigating quickly, because it can mean the well is drawing from a disturbed level or the casing has been compromised.
Well Pumps at Ken’s Distributing
Ken’s Distributing supplies submersible and surface well pumps across the Franklin Electric range, including the components that keep a system running cleanly. If your water has changed and you suspect the pump or its setting rather than the aquifer, send us the symptoms and the well details and we will help work out which it is.
If the pump itself is the next question, our guide to Franklin pumps by application covers the options.