Water Quality Reports – How to understand them

One a year, your water provider is required to provide you with a Consumer Confidence Report (also known as a CCR). This report is due by July 1st.

The information provided in this report includes several key point of information including where your water comes from, any potential health risks and what contaminants may exist.  Typically, these reports will also include disinfectant levels and water hardness.  The purpose of this report is to provide as much information as possible as to the quality of the water you drink.

Unfortunately, the information provided in the CCR (Consumer Confidence Report) can be confusing and difficult to understand.  In this post, we will provide some information to help in understanding your report.  For some of our readers who are on well water or community well system, there is no requirement for a water quality report.  To better understand what is in your water, you will need to perform an independent water quality test.

According to the EPA, there are eight (8) key indicators to focus on.  They have a great document that outlines this and you can view it by clicking here

The eight key indicators are:

  • MCLG/MRDLG (Maximum Contaminant Level Goal): This is the maximum level of contaminants that your drinking water can have without causing any “known” or “expected” health risks.  When comparing this indicator with the “Your Water” column, you want to make sure that your water is lower than this indicator.
  • MCL (Maximum Contaminant Level): Any value above this level is an EPA violation
  • Range (Low / High): As part of the annual testing process, multiple water samples will be collected from within the area.  The “high” and “low” of these will be reported.  This does not specifically identify where these locations are, but it does provide consumers insight as to how different the water quality can be within a specific area.
  • Treatment Technique: This is the indicator of how your water is treated to ensure it is safe to drink.  Chlorine is the most common form of treatment and is usually expressed in parts per million (PPM).  Some municipalities however have moved towards treating with both chlorine and ammonia which creates chloramines.
  • MRDL (Maximum Residual Disinfectant Level):  This is the highest level of “disinfectant” that can be in your water.  As mentioned earlier, the typical disinfectant is chlorine and should normally not exceed 2 parts per million (2 PPM).  As a comparison, a normal swimming pool typically maintains a chlorine level of 1-3 parts per million (PPM).
  • Typical Sources: Another key indicator in you water quality report (CCR) is the typical sources of contaminants. In numerous cases, contaminants discovered in your water are a result of natural erosion, water table changes and other factors. Regardless of the source, the report should identify them.
  • Violation: This indicator is obvious.  If any of the minimum requirements are not met during testing, then a violation should occur.
  • Your water: This is the comparison. A sampling of your water compared to the overall water test. This does not mean that they physically tested your water.  This means that a sample(s) was taken in an area and the results were analyzed.


In closing, virtually all municipalities and water companies are; first and foremost, focused on the health and safety of your water, and the health and safety of their customers.  Water is the most important resource we have and is critical to our survival.  Take time to learn what is in it.