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When should I test my well water?

Municipalities must test their water supplies regularly to ensure the water is safe to drink. However, because there’s no requirement to test a private well except when it’s first drilled or the pump is changed, you’re responsible for making sure your well water is safe for drinking and bathing.
You should test your water on a regular basis. The types of land uses near your well determine which tests you should perform on your water supply.

Water testing suggestions

If you own property with a private water supply, such as a spring or a well, you might consider the following water testing suggestions:

  • Because bacterial levels in the water can change over time, a coliform test should be performed every year.
  • If there’s farming or livestock ranching nearby, nitrates can be found in areas where fertilizers have been applied or livestock waste is found.
  • If children are drinking the water on a regular basis, fluoride levels should be between 1 and 2 milligrams per liter (mg/l). Fluoride levels of less than 1 mg/l may prevent the proper development of teeth, and supplements may be needed. Fluoride levels greater than 4 mg/l can lead to a pitting and staining of the teeth caused by fluorosis.
  • If the bathroom fixtures are stained by the water, check for the following metals:
    • Blue or green stains indicate the presence of copper.
    • Red or rust-colored stains indicate iron is present.
    • Black stains indicate the presence of manganese or zinc.
  • Uranium is naturally occurring in granite formations, which are found throughout Colorado, especially in the foothills. It can be found dissolved in the water of wells in these areas.

If your home uses the city water supply, you might consider the following water test suggestions:

  • Lead.
  • Hardness.
Water Testing Frequently Requested Information.
Private Well Class

Free resources such as classes, webinars and library materials

Drinking Water From Household Wells Document

How wells are polluted, how to protect them, what pollutants contaminate the water and what testing is needed

Drinking Water from Private Wells Website
Water Testing Turnaround Times