Do you want to learn more about the quality of your public water supply, but are not sure where to go?
One of the best ways to educate yourself about local water quality conditions is to obtain a copy of your community's Consumer Confidence Report (CCR). This annual report, which is issued around July 1 each year, provides consumers with detailed information regarding the source of their drinking water and the treatment methods used, as well as the quality of the finished drinking water that was provided to your community during the previous calendar year.
Select one or more of the topics below to learn more about CCR reports:
In 1996, the EPA proposed an amendment to the Safe Drinking Water Act requiring that all community water systems provide their customers with an annual water quality report. This report is designed to give consumers information about the quality of the water they are receiving and allow them to make personal health-based decisions regarding their drinking water consumption.
According to the EPA, each report must provide consumers with the following fundamental information about their drinking water:
Not all items in these reports refer to harmful contaminants. The information often includes characteristics of the water supply that are not health-related. Such things may include measurements of color, odor, pH level (acidity of the water), hardness, alkalinity, temperature, silica, sodium, and potassium.
Most consumers will have copies of these reports mailed directly to their residences on an annual basis. In addition, many communities are posting these reports on the community's website. If you did not receive a copy of this report, call your local water department and request a copy of their most recent summary report.
In order to understand the information presented in your community's annual water quality report, it is helpful to first become familiar with some of the common terminology used to present this information.
Units of Measurement
Water departments often have several ways of expressing the concentration, or amount, of a certain contaminant in drinking water. These expressions also vary depending on the type of contaminant being measured. Here are some units that consumers are likely to see on their water analysis reports:
| mg/L | Milligrams per Liter is one of the most common units used to measure the amount of a contaminant in a water supply. For smaller amounts, micrograms per liter is used (μg/L). One milligram per liter divided by 1,000 is equal to one microgram per liter. 0.001 mg/L = 1 μg/L and 1 mg/L = 1,000 μg/L |
| ppm | Parts per Million is equivalent to saying milligrams per liter. 1 mg/L = 1 ppm. For very small amounts, parts per billion can be used (ppb). One part per million divided by 1,000 is equal to one part per billion. .001 ppm = 1 ppb and 1 μg/L = 1 ppb |
| MFL | Million Fibers per Liter is used to measure asbestos, which exists in the form of tiny fibers. |
| NTU | Nephelometric Turbidity Units measure the turbidity, or clarity, of the water. |
| pCi/L | Pico Curies per Liter is a measurement of radioactivity, used for such contaminants as radium, uranium, and radon. These contaminants emit radioactive waves that may be absorbed by the body. |
| gpg | Grains per gallon refers to the hardness of water. Very hard water has more than ten grains per gallon, and very soft water has less than one grain per gallon. Hardness can also be reported in mg/L. 1 gpg = 17.1 mg/L |
Abbreviations
| AL | Action Level is the concentration of lead or copper in water that determines, in some cases, the treatment requirements that a water system is required to complete. Unlike MCLs, AL violations do not require public notifications. Most high levels of lead and copper, though, are due to household pipes and faucets. |
| MCL | Maximum Contaminant Level is the maximum level of a contaminant that is allowable in public drinking water supplies. Water suppliers are required to notify their patrons when an MCL is exceeded. |
| MCLG | Maximum Contaminant Level Goal is the level of a contaminant in drinking water at which there is no known or anticipated health threat from that contaminant to a person who consumes the water. |
| NA | Not Analyzed can mean that the source water has been deemed non-vulnerable to a specific contaminant or that testing was not required. |
| ND | Not Detected means that none of the contaminant was found in the water sample. Water analysis equipment has detection limits, which refer to the smallest amount of a contaminant that the equipment is capable of detecting. |
| TT | Treatment Technique is the set of procedures that public water suppliers must follow to ensure that a contaminant is controlled in their drinking water supplies. It can include the addition of water treatment chemicals to the water. |
How to Interpret the Results on Your Report
Most water quality reports contain several columns of information. A brief description of the various columns is provided below.
To interpret the information on your report, first identify the name of the contaminant and then compare the level shown in the "amount detected" column against the level shown in the "MCL" column. This will help you to determine whether or not a particular contaminant is present in your drinking water at a level that is near or exceeds federal or state guidelines.
Secondly, you can also compare the "amount detected" in your water supply against the level shown in the "MCLG" column. Keep in mind that the MCLG level is simply a target goal, not a requirement. Water utilities are currently required to keep contaminant levels below the MCL level, but not the MCLG level.
Who can I contact if I have questions about the specific water treatment techniques used in my community or if I have questions about the test results presented on this report?
The best source of information on these topics would be your local water supplier. Their staff would be the most knowledgeable source for water quality information specific to your community. They will be able to answer questions and provide you with information on local water quality conditions and the type of treatment processes used in your community, as well as how often the water supply is analyzed for specific contaminants.
Who can I contact if I have questions about government regulations of drinking water supplies or water quality in general?
If you have questions regarding the development of the MCL and MCLG levels shown on your report, you can contact the EPA's safe drinking water hotline at 1-800-426-4791. The staff at this hotline number can address questions about federal drinking water standards and provide general information on water quality in the United States.
The NSF Consumer Affairs Office can also address questions on these and other water quality topics. You can contact our Consumer Affairs Office via our toll-free consumer hotline at 1-800-673-8010 or send them an email at info@nsf.org.
I have a home water treatment system (or am interested in purchasing one). Where can I go for independent information on these products?
Some consumers may have issues related to the taste, odor, or presence of a particular contaminant in their drinking water supply. If you have or are considering the use of a home water treatment device, we encourage you to visit the Drinking Water Treatment section of our website.
NSF is the leading independent tester of home water treatment. We evaluate hundreds of brands of water treatment devices each year to ensure they meet the design and performance requirements of national public health standards. Consumers can be confident that home water treatment devices that carry NSF certification will actually reduce the contaminants as claimed by the manufacturer on the product label. In addition, you can also be assured that the product itself is not adding harmful levels of contaminants to the water.
Unlike many other product testing programs, NSF-certified products must be re-certified each year; this allows us to assure consumers that the products they are using continue to meet the strict national standards for public health and safety.
Although we do not make product recommendations, the NSF Consumer Affairs Office is available to answer general questions regarding home water treatment products and the testing our organization performs on these devices. You can contact our Consumer Affairs Office via our toll-free consumer hotline at 1-800-673-8010 or via email at info@nsf.org.
