2011 Drinking Water Report


Jan. 1–Dec. 31, 2011

Each year, the City of Eden Prairie issues the results of monitoring done on its drinking water to advance consumers’ understanding of drinking water and heighten awareness of the need to protect precious water resources. The monitoring results in this report cover the period from January 1 to December 31, 2011. The purpose of this report is to advance consumers' understanding of drinking water and heighten awareness of the need to protect precious water resources.

In an effort to reduce the environmental impact of producing this report, the City of Eden Prairie is now providing the annual Drinking Water Report in an online version only - please consider the environment before printing this page.

The Minnesota Department of Health (MDH) has determined that the source(s) used to supply the City's drinking water is not particularly susceptible to contamination. If you wish to obtain the entire source water assessment, please call 651-201-4700 or 1-800-818-9318 (and press 5) during normal business hours. You can also view it online at health.state.mn.us/divs/eh/water/swp/swa.

For more information about the City of Eden Prairie 2011 Drinking Water Report, or to obtain a printed copy, contact the City’s Water Treatment Supervisor Joe Dusek at 952-294-5902 or jdusek@edenprairie.org. If you wish to learn more about scheduling a tour of the water plant or about the City's lawn watering policies, please contact the City's Environmental Coordinator Leslie Stovring at 952-949-8327 or lstovring@edenprairie.org.

Water Quality Monitoring Results - Summary

No contaminants were detected at levels that violated federal drinking water standards. However, some contaminants were detected in trace amounts that were below legal limits. The tables at the end of this report show the contaminants that were detected in trace amounts last year. Some contaminants are sampled less frequently than once per year because the concentrations of these contaminants do not change frequently. As a result, not all contaminants were sampled for in 2011. If any of these contaminants were detected the last time they were sampled for, they are included in the table along with the date that the detection occurred. Abbreviations are listed at the bottom of this report.

Contaminant (units) MRDLG MRDL **** ***** Typical Source of Contaminant
Chlorine (ppm)





Water additive used to control microbes


**** Highest and Lowest Monthly Average
***** Highest Quarterly Average

Contaminant (units) MCLG MCL Level Found Typical Source of Contaminant
Range (2011) Average/ Result*

Barium (ppm)





Discharge of drilling wastes; Discharge from metal refineries; Erosion of natural deposits
cis-1,2-Dichloroethylene (ppb)





Discharge from industrial chemical factories.
Fluoride (ppm)





Minnesota requires all municipal water systems to add fluoride to drinking water to promote strong teeth; Erosion of natural deposits; Discharge from fertilizer and aluminum factories.
Haloacetic Acids (HAA5) (ppb)





By-product of drinking water disinfection
TTHM (Total trihalomethanes) (ppb)





By-product of drinking water chlorination.


* This is the value used to determine compliance with federal standards. It is sometimes the highest value detected and sometimes is an average of all the detected values. If it is an average, it may contain sampling results from the previous year.

Inorganic Contaminants – Source Water (Household Testing)
Contaminant (units)





90% Level


# sites over AL


Typical Source of Contaminant

Copper (ppm) (07/29/2010) 1.3 1.3 0.02 0 out of 30 Corrosion of household plumbing systems; Erosion of natural deposits.
Lead (ppb) (07/29/2010) 0 15 1.3 0 out of 30 Corrosion of household plumbing systems; Erosion of natural deposits.


If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. The City of Eden Prairie is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components.

When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested.

Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the EPA's Safe Drinking Water Hotline.

Some contaminants do not have Maximum Contaminant Levels (MCLs) established for them. These “Unregulated Contaminates” are assessed using state standards known as health risk limits to determine if they pose a threat to human health. If unacceptable levels of an unregulated contaminant are found, the response is the same as if an MCL has been exceeded; the water system must inform its customers and take other corrective actions. In the table that follows are the unregulated contaminants that were detected.

Unregulated Contaminants
Contaminant (units) Level Found Typical Source of Contaminant


Range (2011)

Average / Result

Sodium (ppm) (3/10/2009)



Erosion of natural deposits.
Sulfate (ppm) (3/10/2009)



Erosion of natural deposits.


Monitoring for unregulated contaminants as required by U.S. Environmental Protection Agency Rules (40 CFR 141.40) was conducted in 2011. Results of the unregulated contaminant monitoring are available upon request from Cindy Swanson, Minnesota Department of Health at 651-201-4656.

Compliance with National Primary Drinking Water Regulations

The sources of drinking water (both tap water and bottled water) include rivers, lakes, streams, ponds, reservoirs, springs and wells. As water travels over the surface of the land or through the ground, it dissolves naturally-occurring minerals, and in some cases, radioactive materials, and can pick up substances resulting from the presence of animals or from human activity.

In order to ensure that tap water is safe to drink, the U.S. Environmental Protection Agency (EPA) prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. Food and Drug Administration (FDA) regulations establish limits for contaminants in bottled water which must provide the same protection for public health.

Drinking water, including bottled water, may reasonable be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the EPA's Safe Drinking Water Hotline at 1-800-426-4791.

Some people may be more vulnerable to contaminants in drinking water than the general population. Immuno-compromised persons, such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly and infants, can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. EPA/CDC guidelines on appropriate means to lessen the risk of infection by Cryptosporidium and other microbial contaminants are available from the Safe Drinking Water Hotline at 1-800-426-4791.

Key to Abbreviations

AL – Action Level: The concentration of a contaminant which, if exceeded, triggers treatment or other requirement which a water system must follow.

MCL – Maximum Contaminant Level: The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to the MCLGs as feasible using the best available treatment technology.

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

MRDL – Maximum Residual Disinfectant Level.

MRDLG – Maximum Residual Disinfectant Level Goal.

N/A – Not Applicable (does not apply).

90th Percentile Level – This is the value obtained after disregarding 10 percent of the samples taken that had the highest levels. (For example, in a situation in which 10 samples were taken, the 90th percentile level is determined by disregarding the highest result, which represents 10 percent of the samples.) Note: In situations in which only 5 samples are taken, the average of the two with the highest levels is taken to determine the 90th percentile level.

nd – No Detection.

ppb – Parts per billion, which can also be expressed as micrograms per liter (ug/l).

ppm – Parts per million, which can also be expressed as milligrams per liter (mg/l).