Testing Wells to Safeguard Your Water

Testing Frequency

Test your private well, annually is best, for total coliform bacteria, nitrates, total dissolved solids, and pH levels. If you suspect the presence of other contaminants, you should test for those also. You can also contact your local health department to find out what substances may be common in your area's groundwater.

You may want to test more frequently if small children or elderly adults live in your house or if someone in your house is pregnant or nursing. These segments of the population are often more vulnerable to pollutants than others.

You should also test your private well immediately if:

• There are known problems with ground water or drinking water in your area
• Conditions near your well have changed significantly (i.e. flooding, land disturbances,
• and new construction or industrial activity)
• You replace or repair any part of your well system.
• You notice a change in your water quality (i.e. odor, color, taste).

Identifying reasons to test your water

The chart below lists common conditions or nearby activities that well owners should be aware of and the substance(s) that you should consider testing for to ensure your well is safe. Not all of the substances listed pose an immediate or long term health problem, some impact quality of life only such as appearance, taste, and odor.

Conditions or Nearby Activities:	Test for:
Recurring gastro-intestinal illness	Coliform bacteria
Household plumbing or service lines that contain lead	pH, lead, copper
Radon in indoor air or region is radon rich	Radon
Corrosion of pipes, plumbing	Corrosion, pH, lead
Nearby areas of intensive agriculture	Nitrate, nitrite, pesticides, coliform bacteria
Coal or other mining operations nearby	Metals, pH, corrosion
Gas drilling operations nearby	Chloride, sodium, barium, strontium
Dump, junkyard, landfill, factory, gas station or dry-cleaning operation nearby	Volatile organic compounds, total dissolved solids, pH, sulfate, chloride, metals
Odor of gasoline or fuel oil, and near gas station or buried fuel tanks	Volatile organic compounds
Objectionable taste or smell	Hydrogen sulfide, corrosion, metals
Stained plumbing fixtures, laundry	Iron, copper, manganese
Salty taste and seawater, or a heavily salted roadway nearby	Chloride, total dissolved solids, sodium
Scaly residues, soaps don’t lather	Hardness
Rapid wear of water treatment equipment	pH, corrosion
Water softener needed to treat hardness	Manganese, iron
Water appears cloudy, frothy or colored	Color, detergents

Prevent water well pollution

Protect your water supply by carefully managing activities near the water source. For households using a domestic well, this includes keeping contaminants away from sinkholes and the well itself. Keep hazardous chemicals out of septic systems.

• Slope the area around the well to drain surface runoff away from the well.  
• Install a well cap or sanitary seal to prevent unauthorized use of, or entry into, the well.
• Keep accurate records of well maintenance, such as disinfection or sediment removal, that may require the use of chemicals in the well.
• Hire a certified well driller for any new well construction, modification, or abandonment and closure.
• Avoid mixing or using pesticides, fertilizers, herbicides, degreasers, fuels, and other pollutants near the well.
• Do not dispose of wastes in dry wells or in abandoned wells.
• Do not cut off the well casing below the land surface.
• Pump and inspect septic systems as often as recommended by your local health department. 
• Never dispose of harsh chemicals, solvents, petroleum products, or pesticides in a septic system or dry well.  
• Periodically inspect exposed parts of the well for problems such as:
• • Cracked, corroded or damaged well casing
  • Broken or missing well cap
  • Settling and cracking of surface seals
• Regularly check the integrity of any above ground and underground storage tanks that hold home heating oil, diesel, or gasoline on your property
• Check with your local health department or environmental agency to ensure activities and industry on or near your property are set a safe distance from your well.