Well Water Systems

In some areas of Jefferson County, a substantial number of residential dwellings receive water from private wells. Although most well water is of good quality, there are several contaminants, both naturally occurring and otherwise, which may affect the suitability of the water supply. Jefferson County Public Health recommends that well water be tested for certain contaminants. Information on water testing can be found on the Colorado Department of Public Health and Environment's website.

You're the Inspector

Unlike public water supplies which are continuously monitored, the responsibility for assuring a safe supply of water from private wells rests solely with the homeowner. An annual checkup by a qualified water well contractor is the best way to ensure problem-free service and quality water. In Colorado, there are no regulatory standards governing the quality of private water supplies. The maximum contaminant levels (MCLs) are set by the State and Federal governments and are based upon reasonable health impacts. Individual wells cannot be condemned by any governmental agency due to poor water quality.

  1. Bacteria
  2. Fluoride
  3. Giardia
  4. Nitrate
  5. Radiation


Present throughout the soil are naturally occurring bacteria (referred to as coliforms) which may enter the water supply of individual wells. Although coliform bacteria are not pathogenic (disease-causing) themselves, their presence may indicate that other, more difficult to detect bacteria or viruses are also present. The level of coliform bacteria in a sample is reported as "present" or "absent," rather than reporting the number of bacteria.

Testing Your Well Water

Typical well water tests for most areas should include bacteria, nitrate and fluorides. You may consult a private laboratory for testing or you may order bottles from the State Health Department lab by calling 303-692-3074. Find more information in the When to Test Your Well brochure (PDF) and the How to Interpret Water Test Results for a Private Well brochure (PDF).

These bottles and the accompanying forms will be mailed to you. Follow the directions for taking the sample and completing the forms. Then, either take the bottles to the State lab at 8100 Lowry Boulevard, or drop them off at the Jefferson County Public Health Lakewood office for transport to the State lab. The transportation fee is $10 (cash or check) and you must have the bottles in our office no later than 8:10 a.m. Be sure to bring the completed lab forms and a check for the appropriate amount (cash not accepted). Call 303-232-6301 for further information.


Although not directly related to water quality, quantity is an important consideration in judging the suitability of individual wells. The amount of water obtained from a well is related to how much the well produces and how much storage is available. For example, even a low-producing well may prove acceptable if there is sufficient storage of water to meet the peak demand. The actual gallonage requirements are based upon the individual needs of you or your family.

On average, a typical family uses 50 gallons of water per person per day. This figure does not include outside activities such as lawn watering. Many well permits, however, do not allow for irrigation, individual permits must be referenced regarding this type of use.

Water Treatment

If your water contains contaminants that exceed safe drinking water standards, treatment methods are available for household use. Contact Environmental Health Services at Jefferson County Public Health, 303-232-6301, for further assistance in determining whether treatment is desirable and, if so, what methods are available.