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North Castle Daily News

Why Test Private Well Water?

November 9, 2015
Over ninety percent of all North Castle’s homeowners use well water. It’s important to understand that a standard well water test is the only reliable way to know if your water is safe to drink.

Westchester County’s 2007 Private Well Water Testing Law applies to residential properties that are served by private wells. A well water test is required as part of a selling contract. The law also requires well water testing on a regular ongoing basis for residential rental properties in Westchester.

The New York Department of Health suggest residents test well water sources yearly for contaminants such as total coliform bacteria, nitrate, chloride and lead. Total coliform, which may shows up in a water test, can result from a variety of sources. But a positive total coliform sample should be considered an indication of pollution in any water supply.

Fecal coliform bacteria, in the strain of E. Coli, is a bacteria which is found in soil and water that has been contaminated by human or animal waste. Although most coliform does not cause diseases, some rare strains of E. coli can cause serious illnesses. If E. coli is present in well water, there is a risk of contracting a waterborne illness. Positive fecal coliform results, especially positive E. Coli results, should be considered an indication of fecal matter in a well. When coliform has been detected, repairs to modify the water system are required.

The New York Department of Health says there may be various kinds of well defects that allow coliform contamination. These issues should be investigated and then repaired, or replaced, if necessary:

• Seals around wires or pipes of defective well caps may let in contaminants.
• Contaminants that have not been filtered through the soil can seep through cracks or holes in the water well casing.  
• Well flooding is a common problem for well heads located below the ground in frost pits that frequently flood during wet weather.

Westchester’s Private Well Water Testing law requires a remedy to correct any failure in the level of any contaminants. The options to treat for total coliform bacteria include well chlorine disinfection or an ultraviolet (UV) treatment system. Retesting for bacteria to ensure the treatment is adequate is required after a well disinfection or installation of an UV treatment system.

Improper construction or a failing septic system can be harmful to groundwater. There are over eighty percent of North Castle’s homes on septic systems. A good septic maintenance plan recommended by the Westchester County Department of Health includes pumping a septic system every two to three years, depending upon the usage.

Since bacterial contamination is most likely to show up during wet weather, experts suggest doing a well test following a rainy period. Westchester County government says the estimated average cost for a well water test is between $400 to $450.