How To Read Residential Well Water Test Results

How to read well water test results

Learn what to look for in an annual well water test.

The Environmental Protection Agency (EPA) recommends that homeowners have an annual well water test to check the quality of their water supply. If you've ever received your water from a municipal water supply, you've probably seen an annual water quality report included in your bill. As a homeowner, if you receive your water from a private well, an annual water test is your responsibility.

Whether you receive your water quality report from your municipal water department, or a private state certified testing lab, it's an important source of information that rates the quality and safety of your water supply. Your report highlights everything from the source of your water (if you receive municipal water) to the levels of any contaminants found along with the potential health effects.

Put simply, your water quality report is the first line of defense in knowing what's going on with your home's water. Understanding it is critical to protecting the health and safety of you and your family.

Understanding your well water test

Your report will contain a detailed chart breaking down any contaminants detected. It contains various abbreviations and codes. Knowing what these mean can help you to understand what's in your water.

Look for the following on your water test results:

Contaminant name – The substances being tested for in your water.

MCL (maximum contaminant level)  - This is the highest level of any contaminant permitted in your water.

MCLG (maximum contaminant level goal) – This is the minimum contaminant level allowed for which there is no known or expected health risk. MCLGs provide you with the boundary level for each contaminant detected.

Violation – If a contaminant exceeds the MCL you will see a yes in this column.

The EPA has set MCLs as a guideline for healthy drinking water. If testing determines that you have levels at or above the MCLG for certain contaminants, immediately seek to remediate the problem by installing a water treatment system.

What contaminants might a well water test detect?

Contaminants can vary geologically, geographically and by proximity to sources of pollution like agricultural businesses, gas stations, industrial facilities and even through improper disposal of household chemicals. Your local well water professional should have knowledge particular contaminants that may be common in your location.

Contaminants can occur naturally or can be caused by human activity. For example, here in New England, we often see naturally occurring radon and arsenic levels that are higher than normal. Here are a few of the potential contaminants you may find on your well water testing report.

Arsenic – Arsenic is naturally occurring. It can leach into well water through rocks, soil, air, water, plants, and animals, as well as human activity. Exposure can cause both long and short term health effects. The maximum level for arsenic in water is 0.10 milligrams per liter (mg/l) Learn More >

Chloride – Chlorides do not cause health problems but can result in unpleasant salty tasting water if levels are high. Extreme chloride levels can, however, have a detrimental effect on metabolism. 14 mg/l is normal. The maximum level in well water is 250 mg/l Learn More >

Coliforms – If coliforms are present, at any level, it's a cause for concern and immediate action. Wells are constructed to be coliform free. If coliform is detected it means that surface water has somehow leaked into the well. The federal guideline states that safe drinking water should not contain more than 10 total coliform bacteria per 100 ml of water. Test results will either show: (A) meaning coliform is absent, or (P) meaning it is present. Learn More >

Water hardness – Calcium and magnesium cause water hardness. The presence of these naturally occurring elements does not pose a health hazard, but can be a nuisance. Hard water can reduce the life of household appliances and also cause staining, leave residues and diminish the effectiveness of detergents. Low (soft water) 0 – 75 mg/l , Moderate 76 – 150, Hard 151 – 250, very hard 251+. Learn More >

Volatile Organic Compounds (VOCs)There should never be any VOCs present in well water. Period! The presence of VOCs may indicate contamination by petroleum products, industrial solvents, or chemical byproducts. The presence of any of these compounds requires immediate attention and may pose a serious health risk. Learn More >

These are just a few of the possible contaminants you may find through testing. Others include copper, E. coli, fluoride, manganese, nitrates, radon, and sodium. A well water test will also check overall pH, and turbidity or cloudiness.

An annual well water test is the best way to keep your water supply safe. Understanding how to read well water test results is the first step. At Skillings & Sons we've been helping homeowners in Massachusetts and New Hampshire to arrange well water testing, interpret results, and remedy well water issues for years. We can help you too. We offer a full range of water treatment systems that can help keep your water safe. If you'd like to learn more,  just give us a call at 1-800-441-6281 today. We're ready to help!