Water quality is a term used to describe the chemical, physical, and biological characteristics of water, usually in respect to its suitability for a particular purpose. Although scientific measurements are used to define a water's quality, it's not a simple thing to say that "this is good water ," or "this is bad water ." After all, water that is perfectly good to wash a car with may not be good enough to serve as drinking water. When the average person asks about water quality, they probably want to know if the water is good enough to drink, cook, or wash with. Or they want to know if the quality of our natural waters are suitable for aquatic plants, fish and animals.

Ground water may contain some natural impurities or contaminants, even with no human activity or pollution. Natural contaminants can come from many conditions in the watershed or in the ground. Because water is such an excellent solvent it can contain lots of dissolved chemicals. And since ground water moves through rocks and subsurface soil, it has a lot of opportunity to dissolve substances as it moves, such as magnesium, calcium and chlorides. For that reason, ground water will often have more dissolved substances than surface water will. Some ground water naturally contains dissolved elements such as arsenic, boron, selenium, or radon. Whether these natural contaminants are health problems depends on the amount of the substance present.

In addition to natural contaminants, ground water is often polluted by human activities such as:

  • Improper use of fertilizers, animal manures, herbicides, insecticides, and pesticides. (gardens and flower beds too close to the well)
  • Improperly built or poorly located and/or maintained septic systems for household wastewater.
  • Leaking or abandoned aboveground/underground storage tanks and piping.
  • Surface spills of fuels and oils
  • Storm-water drains that discharge chemicals to ground water
  • Improper disposal or storage of wastes.
  • Improper disposal of household hazardous wastes such as paint, solvents, cleaners etc.
  • Road salts

Noticeable problems

  • Scale or scum from calcium or magnesium salts in water.
  • Unclear/turbid water from dirt, clay salts, silt or rust in water.
  • Green stains on sinks or faucets caused by high acidity.
  • Brown-red stains on sinks, dishwasher, or clothes in wash points to dissolved iron in water.
  • Cloudy water that clears upon standing may have air bubbles from poorly working pump or problem with filters.
  • Salty or brackish taste from high sodium content in water.
  • Alkali/soapy taste from dissolved alkaline minerals in water.
  • Metallic taste from acidity or high iron content in water.
  • Chemical taste from industrial chemicals or pesticides.
  • A rotten egg odor can be from dissolved hydrogen sulfide gas or certain bacteria in your water. If the smell only comes with hot water it is likely from a part in your hot water heater.
  • A detergent odor and water that foams when drawn could be seepage from septic tanks into your ground water well.
  • A gasoline or oil smell indicates fuel oil or gasoline likely seeping from a tank into the water supply.
  • Methane gas or musty/earthy smell from decaying organic matter in water

Unnoticeable problems

Many serious problems can only be found by laboratory testing of water.

  • bacteria
  • heavy metals and minerals
  • nitrates
  • radon
  • pesticides, herbicides and other chemicals

Separation Distances

Because of all the above noted forms of contamination it is important to locate wells a safe distance from these possible sources or locate the sources of contamination as far as possible from existing wells. Regulation 903 prescribes that water wells be located as follows;

  • at least 15 metres (50 feet) for drilled wells with watertight casings that extend 6 metres (20 feet) or more below ground level.
  • at least 30 metres (100 feet) for all other wells.