The importance of clean, safe drinking water cannot be overstated.
Drinking Water and Health
The majority of New Mexicans are provided high quality drinking water by community water systems. Community water system is a type of public water system that supplies water for human consumption to at least 15 service connections and more than 25 people year round. The U.S. Environmental Protection Agency (U.S. EPA) sets regulations for monitoring and treating drinking water delivered by these systems. There are water quality standards and monitoring requirements for over 90 contaminants.
About 20 percent of the population in New Mexico (or estimated 350,000 people) receives their water from a private well. According to the office of the state engineer, private wells use 11.6 billion gallons of water per year , which is estimated at about 10% of the drinking water usage in New Mexico. The water quality from private wells is not monitored or regulated by the EPA or the state. It is the responsibility of the home owner to ensure that their water is safe for human consumption.
Community Drinking Water Data from NM EPHT
On the Community Drinking Water Data
page you will find information about the levels of five contaminants in drinking water: arsenic, nitrate, disinfection by-products, lead, and uranium. These contaminants were selected because they occur more frequently in drinking water at levels which may be of public health concern. The information focuses on community water supplies, as there are limited data on water contaminants for private wells that are not monitored by the EPA or the state.
Drinking water contaminants, even at very low concentrations, may affect the health of many people. Since contamination in a single drinking water system can affect many people at once, drinking water quality is an important public health issue. People can be exposed to contaminants in water not only by drinking the water, but also by eating foods prepared with the water, eating produce or meats that were grown or raised on the contaminated water, breathing chemicals that have vaporized from the water (when showering, bathing, or flushing toilets), or absorbing them through direct contact with skin while showering or bathing.
The type and severity of the health problem depends on: the specific contaminant, the concentration of the contaminant in the water, the length of time a person is exposed to the contaminant and the person's individual susceptibility. If a person is exposed to a high enough level of a contaminant over a long enough period of time, they may become ill. The necessary dose and time required for someone to become ill depends on many different factors. Effects can be seen short-term (weeks) and/or long-term (many months or years). There are many types of health problems that can result from exposure to contaminants.
This percentage is an estimate based on the number of liquid waste permits held by the New Mexico Environment Department. As of 2000, the Office of the State Engineer states that they have issued 140,000 private well permits since 1953.
NMOSE, 2008. New Mexico Water Uses by Categories 2005.
Technical Report 52. (1.3 MB)
How can contaminants get into drinking water?
Drinking water contamination can be natural or anthropogenic (man-made) in origin. An example of a common source of natural contamination is the minerals which naturally occur in the aquifer, such as arsenic or uranium. Man-made sources of contamination include: septic tanks, leaky underground storage tanks, and run off from fields where fertilizers and/or pesticides have been used. In some cases, an action, such as applying fertilizer, will cause a naturally occurring contaminant, such as arsenic or uranium, to mobilize and end up in the water supply system.
This Web site includes information on the number of people that use community water systems for their water supply and contaminant levels over time, using data from state and EPA public drinking water programs.
Currently, we present summary statistics about community water systems within the state of New Mexico. This summary does not present data on whether or not individuals are actually being exposed to these contaminants or any health effects potentially resulting from drinking water contamination.
For more information on how contaminants may enter drinking water systems see the
EPA Watershed Web site (http://www.epa.gov/owow/watershed/). For more information on drinking water exposure see the Centers for Disease Control and Prevention (CDC) Safe Water Web site (http://cfpub.epa.gov/safewater/sourcewater/) and the New Mexico Department of Health Environmental Health Epidemiology Bureau Web site (http://www.health.state.nm.us/eheb/). Or, call the Environmental Health Epidemiology Bureau Toll Free at 1-888-878-8992.
Who is at risk?
The risk of developing a specific disease depends on many factors such as:
- The specific contaminant, the level and potency of that contaminant.
- The way the contaminant enters the body (ingestion, inhalation or direct skin contact).
- The person's individual susceptibility.
- Sensitive people, such as the elderly, children, pregnant women, and immune compromised, are more likely to suffer ill effects than the rest of the population.
The specific health risks associated with the contaminants presented on this Web site are discussed in detail on the following page, Drinking Water Contaminants.
Community Drinking Water Monitoring
Community water systems are required to provide drinking water that meets standards established under the Safe Drinking Water Act. The U.S. Environmental Protection Agency (EPA) sets drinking water standards for individual contaminants and groups of contaminants. Typically, these standards protect public health by limiting the levels of contaminants in drinking water. For public water systems (including community water systems), the federal government has established legally enforceable regulatory limits – National Primary Drinking Water Regulations (NPDWR) – for over 90 chemical, radioactive, and microbial contaminants in drinking water. These regulatory limits originate from the Safe Drinking Water Act and govern public water systems. New Mexico has adopted the federal standards. Users of private wells or other private water sources are solely responsible for monitoring and maintaining the quality of their water supply.
Public water suppliers are required to monitor the quality of the water they supply, and consumers must be notified if a primary drinking water standard is exceeded. There are two types of EPA standards:
- Primary drinking water standards (Maximum Contaminant Levels or MCL) are health-based and enforceable.
- Secondary drinking water standards (Secondary Maximum Contaminant Levels or SMCL) are based on aesthetics such as color, odor, and taste of the water. They are guidelines, not enforceable limits.
For more information on the Drinking Water Standards or the Safe Drinking Water Act see the EPA Web site
Safe Drinking Water Act Guide. (293.0 KB)
Every year, community water suppliers send customers a "Consumer Confidence Report" that contains information about the quality of water. It includes information on where the water comes from, how it is treated, a list of the chemicals they test for, and the highest concentration of each chemical that they found in the past year. If you did not receive a "Consumer Confidence Report" you can obtain one by contacting your water supplier.
When a water system has a problem that might pose a risk to public health, they are required to notify their customers. The most common problems are contaminant levels that exceed health standards (water quality violation) or problems with the water treatment system (treatment technique violation). If it is a serious situation, they must notify the public within 24 hours; for less serious problems they must notify the public within 30 days. In some circumstances water systems must work with the state drinking water program to prevent a more serious problem, even if there has not been a violation.
For more information on public notifications of drinking water problems see
Public Notification Rule: A Quick Reference Guide. (344.6 KB)
If your community water system has notified you that there has been a problem you should carefully follow the advice given by the water system and the local public health officials. If you think there is a problem with your drinking water you should call your water provider or the New Mexico Environment Department Drinking Water Bureau.
See their Web site, http://www.nmenv.state.nm.us/dwb/, or call the Drinking Water Bureau Toll Free at 1-877-654-8720.
Although consumers that drink water supplied by community water systems can have confidence in the water quality due to the monitoring and treatment of the water before distribution, private well owners cannot. Private well owners are solely responsible for the quality of the water consumed from their wells.
Levels of various naturally-occurring and anthropogenic contaminants in New Mexico ground water, including arsenic, uranium, manganese, nitrates, fluoride, sulfate, and bacteria might be elevated above the Environmental Protection Agency (EPA) Safe Drinking Water standards. 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.
To assure that the water is safe for human consumption, well owners should periodically test their wells. Learn more about well testing, filtration, and get reosurces for well owners.
In New Mexico, the State Environment Department performs water fairs where a few of these constituents can be tested for free. Learn more.
Drinking Water Contaminants: Arsenic
Other Contaminants of Concern
Community Water System (CWS) Data
Resources for Well Owners
EPA Web Site
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