Well Water on the South Shore

Many homes on the South Shore of Massachusetts draw water from a private well instead of a town system. Private well water is not regulated or routinely tested by a public utility, so the homeowner is responsible for knowing what is in it. Here is a plain-language overview of common well water problems, why they show up, how to test, and when treatment makes sense.

What well water can contain

• Iron: orange or brown stains on fixtures and laundry, and a metallic taste.
• Sulfur (hydrogen sulfide): a rotten-egg smell, often stronger with hot water.
• Manganese: black or dark brown staining and a bitter taste.
• Coliform bacteria: an indicator that surface water or other contamination may be reaching the well. You can't see, smell or taste it.
• PFAS: a group of man-made "forever chemicals" that have been found in some Massachusetts water supplies. Only a lab test can detect them.
• Hardness: calcium and magnesium that leave scale and spots.
• Low pH (acidic water): can corrode copper plumbing, causing blue-green stains and pinhole leaks.
• Arsenic and radon: naturally occurring in some New England groundwater and bedrock. Both are invisible and need a lab test.

Why South Shore wells see these issues

Groundwater picks up whatever is in the soil and rock it moves through. Naturally occurring minerals such as iron and manganese are common in New England groundwater, and the region's water tends to be soft-to-acidic in many areas, which is why low pH comes up often. Shallow private wells can also be more exposed to surface influences like septic systems, road runoff and nearby land use. Every well is different, even between neighbors, so the only way to know your water is to test it.

How to test well water in Massachusetts

For a full picture, use a laboratory certified by the Massachusetts Department of Environmental Protection (MassDEP). MassDEP recommends that private well owners test their water regularly, and it's a good idea to test after any change in taste, smell or color, after flooding, or when buying or selling a home.

A free in-home water screen is a helpful first step. It can quickly check things like hardness, iron, pH and total dissolved solids so you know where to start. It is not a substitute for a certified lab test for bacteria, PFAS, arsenic or radon.

When treatment is needed

Treatment makes sense when a test shows a health-related contaminant above recommended levels, or when nuisance problems like staining, odor or scale are affecting your home. The right system depends on the results:

• Taste, odor and chlorine-type issues: whole-home carbon filtration.
• Hardness plus general filtration: whole-home filter and softener.
• Wells needing broader treatment, including UV disinfection for bacteria: the full stack with UV.

Avoid buying equipment before you know what's in your water. A system sized for the wrong problem wastes money and may not fix anything.

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