Skip directly to searchSkip directly to the site navigationSkip directly to the page's main content

Private Wells Testing


Make your drinking water quality a health priority for you and your family. The best way to know if drinking water from a private drinking well is safe to drink is by testing it.

If you have a private well, regular water quality testing is very important. Many contaminants cannot be identified by taste or odor, making it difficult for homeowners to know if the water quality of their well has changed. The Environmental Protection Agency (EPA) does not regulate private wells and many states and towns do not require periodic sampling of private wells after they are initially installed. This makes it the responsibility of homeowners to periodically test their well for water contamination.

Common water quality tests check for germs such as E. Coli, and chemicals such as nitrates, arsenic, uranium, lead, and fluoride by taking a sample of water from your well or from your drinking water source in your home such as the kitchen sink. If your well water smells, tastes and looks fine, you should still have it tested. Often germs and chemicals are unnoticed and the only way to find these is through testing. If germs are in your drinking water, they can cause abdominal cramping and diarrhea, for example.

Levels of various naturally-occurring and man-made contaminants in New Mexico ground water, including arsenic, uranium, manganese, nitrates, fluoride, sulfate, and bacteria might be elevated above the EPA Safe Drinking Water standards.

Per- and polyfluoroalkyl substances (PFAS)
, including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), are emerging chemicals that may be found in ground water from some areas. For decades, PFAS have widely been used in many industrial and consumer products such as cookware, stain resistant fabric and carpet, some food packaging, and specialized foam (AFFF) that is used for controlling petroleum-based fires. PFOA and PFOS are the most studied PFAS. Although, companies in the United States have stopped making PFOS and PFOA, PFAS are found in a variety of products and once released PFAS persist in the environment for many years. They can move through soil and contaminate groundwater.

Ongoing drought conditions and aquifer mining have raised further concern that increases in contaminants may occur in the absence of significant ground water recharge events. This is another key reason to test your drinking water.

About 20 percent of New Mexicans receive their water from private wells, which are not tested routinely. There are some options for New Mexicans to test their water. They can take their water to certified laboratories and take the opportunities available through state-sponsored water fair community events and individual testing opportunities from the New Mexico Environment Department.

Community Testing Events - Well Water Test Fairs

To support well owners in New Mexico, the state Department of Health supports the state Environment Department's Water Test Fair program, which periodically offers testing for constituents which may be naturally occurring or result from sources including fertilizer, animal waste, septic tanks, and refuse dumps. Free testing for: arsenic, fluoride, sulfate, nitrate, iron, electrical conductivity, and pH.
Learn about upcoming fairs.

Individual Testing Opportunities - Liquid Waste Program

The New Mexico Environment Department (NMED), Liquid Waste (septic tank) Program provides free testing for nitrate, fluoride, and iron for private well owners at local NMED field offices. Learn about NMED Liquid Waste Program testing.

Private Laboratories- Certified Drinking Water Laboratories

For tests not available through free testing opportunities, it is recommended private well owners test their drinking water quality through labs that have applied for New Mexico certification and have been approved by the New Mexico Environment Department Drinking Water Bureau. See a list of currently certified drinking water laboratories.

The New Mexico Environment Department certifies drinking water testing laboratories for different types of testing. See the most recent list of certified laboratories and their available types of testing.
Per- and polyfluoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), are known as the "forever chemical". PFAS persist in the environment and move through soil and can contaminate groundwater. If you are concerned about the possibility of PFAS in your private well drinking water, it is recommended you get your water tested.
Well Water Recommended Testing Schedule
Make your drinking water quality a health priority for you and your family by testing your water. The table above provides New Mexico Private well users common testing recommendations, and where each type of test is available. Testing recommendations include:

Every Year: Bacteria, Nitrates.

Checking these yearly is a good indicator if your water quality has degraded. This may mean your well casing has cracked or your water has been polluted by animal or human waste.

The best time to test is in spring.

Periodically: Other Chemicals.

Test at least once for arsenic, cadmium, fluoride, iron, lead, manganese, pH and hardness (includes total dissolved solids or electrical conductivity) sulfate, and uranium.

If you live in an area that may be subject to industrial pollution, or near a mine or mill site, test periodically for contaminants of concern, such as arsenic and uranium for many parts of the state.

Other harmful chemicals that you should test for will depend on where your well is located on your property and whether you live in an urban or rural area.

These tests could include testing for lead, mercury, radium, and atrazine, or other pesticides.

There may be other reasons to test your water beyond your regularly scheduled tests, such as:
  • There are known problems with well water in your area.
  • You have experienced problems near your well (i.e., flooding, land disturbances, or nearby waste disposal sites)
  • You replace or repair any part of your well system, such as a pump.
  • Someone in the home is expecting a baby or is nursing.
  • The water changes in smell, taste or color.
  • The well runs dry and then comes back.
  • A spill of chemicals or fuels occurs near your well.
  • You put in a treatment system to fix a water quality problem.
  • New agricultural activities near your well.
  • You just installed the well or you newly purchased property or a home with a well.

Well Water Recommended Testing Schedule
After you test your water it is important to understand what the results mean. The table above provides a simple guide to understanding your test results and some treatment options. Use this water quality interpretation tool, from Colorado State University, to find out what your lab results mean. Choose the US option. The National Groundwater Association provides more information about interpreting your water test results.

This information can help you select an appropriate water treatment system if needed. If test results show that your drinking water contains contaminants at levels above the safe limit, you can improve the quality with treatment. An appropriate water-treatment system or use of an alternative source of drinking water, such as bottled water is recommended. Learn more about water treatment and filtration.
The NM EPHT website is supported by Cooperative Agreement Number, 6 NUE1EH001354 (previously, 5 U38EH000949), funded by the Centers for Disease Control and Prevention (CDC). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of CDC or do not necessarily reflect the official policies of the Department of Health and Human Services, nor does the mention of trade names, commercial practices, or organizations imply endorsement by the U.S. Government. The information published on this website may be reproduced without permission. Please use the following citation: " Retrieved Mon, 27 January 2020 2:19:43 from New Mexico EPHT Tracking Public Web site: https://nmtracking.org/ ".

Content updated: Thu, 5 Dec 2019 15:51:04 MST