South Central Wisconsin
Water Resources

Everything you need to understand our water

Water Resources

Every year the EPA and Wisconsin Department of Natural Resources establish regulations that limit the number of contaminants allowed in drinking water. These reports explain where your water comes from, the quality of your water and what it means for you.

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Our team has helpful tips on how to read your water quality report. Consider us your cheat sheet on how to understand all the scientific mumbo-jumbo.

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Microbial contamination is the presence of bacteria, viruses or other live organisms in your water supply. Not all bacteria or viruses make people sick; some are simply a nuisance, generating taste or odor concerns.

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Inorganic contaminants are compounds such salts, metals, lead or arsenic that can be in the groundwater naturally or introduced by runoff, industrial discharge, mining or farming practices.

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Organic Contaminants

This group of carbon-containing contaminants includes pesticides and herbicides along with fuel byproducts and solvents. These contaminants are NOT naturally occurring and usually enter the water supply through runoff or by absorbing into the soil and eventually making their way downward to groundwater. These chemicals have been traced to landfills, industrial facilities, and septic systems.

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The Environmental Protection Agency regulates this type of contamination to protect public health. Erosion of natural deposits and discharges from nuclear power plants can contribute to radioactivity in groundwater.

Useful Acronyms

Maximum Contaminant Level Goal (MCLG) The level of contamination in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

Maximum Contaminant Level (MCL) The highest level of contamination allowed in drinking water. MCLs are set as close to the maximum contaminant level goals as possible.

Action Level (AL) The concentration of a contaminant which, if exceeded, triggers treatment or other requirements within a public water system.

Maximum Residual Disinfectant Level (MRDL)
The highest level of a disinfectant allowed in drinking water. Evidence suggests that the
addition of a disinfectant is necessary to control microbial contaminants.

Maximum Residual Disinfectant Level Goal (MRDLG) The level of a drinking water disinfectant below which there is no known or expected risk to health.MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.

Treatment Technique (TT) A required process intended to reduce the level of contamination in drinking water.

Data Table Measurement Acronyms

ND = No detection

mrem/year = millirems per year (a measure of radiation absorbed by the body)

pCi/l = picocuries per liter (a measure of radioactivity)

pm = parts per million, or milligrams per liter (mg/l)

ppb = parts per billion, or micrograms per liter (ug/l)

pt = parts per trillion, or nanograms per liter

ppq = parts per quadrillion, or picograms per liter

Wonder What’s in your Water?

Find out exactly what’s in your water. Request a free water analysis today.

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