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 [external link]. Find more information for understanding your well water test results [external link].

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. 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)

There are several options for testing your well water:

  • JCPH is offering water quality testing of private wells free of charge while supplies last. Private water supplies are not regulated by local or state agencies, and there are no regulatory requirements to test your well. However, if you don’t test the water from your well, you don’t know what is in the water you are drinking. JCPH recommends that you test your drinking water well once a year for signs of contamination. JCPH will provide the materials for water quality testing to property owners. The test results will allow JCPH to gain a better understanding of the current water quality conditions throughout the county. The test results will be shared with the property owner along with recommendations for treatment options if contaminants are found in the water. Personal Protected Information such as well owner name, well location and well permit number will not be provided to the public under any condition. To receive water quality test kit fill out the Private Well Water Testing Application.
  • You may also consult a private laboratory for testing or you may order bottles from the State Health Department lab [external link] by calling 303-692-3074. These bottles and the accompanying forms will be mailed to you. Follow the directions for taking the sample and completing the forms. Then, take the bottles to the State lab at 8100 Lowry Boulevard. Unfortunately, JCPH is not offering courier services at this time. PLEASE DO NOT DELIVER WATER SAMPLES TO JCPH FOR TRANSPORT TO THE STATE LAB. Be sure to bring the completed lab forms and a check for the appropriate amount (cash not accepted). 


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.