Water Tips and Facts

The majority of households in 60 of Virginia's 95 counties rely on private water supply systems.

Well Informed Virginia

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Have you just had your well water tested and want to know what the results mean? If so, you've come to the right place. The Well Informed Virginia drinking water interpretation tool has been created to help private well owners and users in Virginia understand water test results in order to determine whether their family's health may be at risk and, if so, available options for response.

Virginia's groundwater is a wonderful resource; in some counties over 80% of the water supply is from private wells, and, overall 22% of Virginia's residents (1.6 million people) rely solely on private wells as their primary source of drinking water. In Virginia, as in many states, private wells are not subject to required ongoing water quality testing such as required for public water supplies. Rather, ongoing well maintenance and testing is at the discretion of the well owner. The Virginia Department of Health (VDH) and the Virginia Household Water Quality Program (VAHWQP) recommend that private well owners regularly test for commonly found pollutants as appropriate.

Helpful terminology

    Well Informed Virginia allows you to interpret what your results mean. Before we begin, here are some useful terms to become familiar with.

  • "Units" – Your test results will usually be listed on your lab report in a unit such as mg/L (milligrams per liter which loosely translates to parts per million), μg/L (micrograms per liter, or parts per billion), or something similar. This tool includes a dropdown menu allowing you to match your test result to the format the lab uses to list your water quality results on the Certificate of Analysis. Make sure to use the correct units when entering your data. Some Bacteriological data is listed as "present" or "absent."
  • "Non-detected" – The laboratory report might indicate that the test parameter, or "analyte" was not detected. Common ways this is indicated on lab reports is "ND" (Not Detected), "BDL" (Below Detection Limit), or by means of a "less than" symbol in front of the result (e.g., < 0.5 mg/L). "Non-detected" does not necessarily mean the analyte is not present, it means that, if present, it is at a lower concentration than the lab can detect.
  • "MCL" – This means Maximum Contaminant Level, which is a health based standard established by the US EPA for drinking water quality. MCLs are legal threshold limits on the amount of a substance allowed in public water systems under the Safe Drinking Water Act. MCLs are not regulated in private wells; however, they are commonly relied upon as benchmarks for private water well quality. Lifetime consumption of drinking water below the MCL is not anticipated to result in quantifiable adverse health effects associated with the contaminant in question.
  • "Secondary MCL" – Secondary MCLs were established by the US EPA for contaminants which are not health threatening but which may cause water to appear cloudy or colored, to have unpleasant taste or odor, or which may cause adverse effects such as corrosion, staining, or scaling of plumbing components.

Using Well Informed Virginia

When you have received your written laboratory report, click the button below to enter your test results from your lab report. WELL INFORMED VIRGINIA will immediately provide you with an evaluation of your well water quality accompanied as appropriate by a list of response options.The information provided by WELL INFORMED VIRGINIA is for informational purposes and does not take place of direct consultation with medical, water treatment, or well inspection professionals. There may be other conditions related to your private well or home plumbing not addressed by this online tool which could be factors related to determination of water treatment or other response to your water test results.