2021 Drinking Water Report

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 Jan. 1 through Dec. 31, 2021.

To reduce the environmental impact of producing this report, the City of Eden Prairie provides the annual Drinking Water Report in an online version only.

Compliance with National Drinking Water Regulations

The City of Eden Prairie provides drinking water to its residents from a groundwater source. This includes 15 wells ranging from 381 to 420 feet deep, that draw water from the Prairie Du Chien-Jordan and Jordan aquifer formations.

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 reasonably 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 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. The developing fetus and therefore pregnant women may also be more vulnerable. 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 800-426-4791.

Drinking Water Sources

Minnesota’s primary drinking water sources are groundwater and surface water. Groundwater is the water found in aquifers beneath the surface of the land. Groundwater supplies 75% of Minnesota’s drinking water. Surface water is the water in lakes, rivers, and streams above the surface of the land. Surface water supplies 25% of Minnesota’s drinking water.

Contaminants can get in drinking water sources from the natural environment and from people’s daily activities. There are five main types of contaminants in drinking water sources.

Microbial contaminants, such as viruses, bacteria and parasites. Sources include sewage treatment plants, septic systems, agricultural livestock operations, pets and wildlife.
Inorganic contaminants include salts and metals from natural sources (e.g., rock and soil), oil and gas production, mining and farming operations, urban stormwater runoff and wastewater discharges.
Pesticides and herbicides are chemicals used to reduce or kill unwanted plants and pests. Sources include agriculture, urban stormwater runoff, and commercial and residential properties.
Organic chemical contaminants include synthetic and volatile organic compounds. Sources include industrial processes and petroleum production, gas stations, urban stormwater runoff and septic systems.
Radioactive contaminants such as radium, thorium and uranium isotopes come from natural sources (e.g., radon gas from soils and rock), mining operations, and oil and gas production.

The City of Eden Prairie provides drinking water to its residents from a groundwater source. This includes 15 groundwater wells ranging from 381- to 420-feet deep that draw water from the Jordan-Prairie du Chien aquifer group.

The Minnesota Department of Health (MDH) has made a determination as to how vulnerable Eden Prairie's systems' source(s) of water may be to future contamination incidents. If you wish to obtain the entire source water assessment, please call 651-201-4700 during normal business hours. View the source water assessment report online.

How to Read Water Quality Data Tables

The tables below show the contaminants which were found last year or the most recent time they were sampled for. They also show the levels of those contaminants and the Environmental Protection Agency’s (EPA) limits. Substances which were tested for but not found are not included in the tables.

Some contaminants are sampled for less than once a year because the levels are not expected to change from year to year. If any of these contaminants were found the last time they were sampled for, they are included in the tables below with the detection date.

The City may have done additional monitoring for contaminants that are not included in the Safe Drinking Water Act. To request a copy of these results, call the Minnesota Department of Health at (MDH) 651-201-4700 between 8 a.m. and 4:30 p.m., Monday through Friday.

Some contaminants are monitored regularly throughout the year and rolling (or moving) annual averages are used to manage compliance. Because of this averaging, there are times where the Range of Detected Test Results for the calendar year is lower than the Highest Average or Highest Single Test Result, because it occurred in the previous calendar year.

Abbreviations are listed at the bottom of this report.

Testing and Monitoring Procedures

Questions

Contact Rick Wahlen, utility operations manager, at 952-949-8530 with questions and information about the City's drinking water, opportunities for public participation in decisions that may affect the quality of water, or to learn about volunteering for the lead and copper household water testing program.

If you wish to learn more about scheduling a tour of the Water Treatment Plant, the City's lawn watering policies or would like a copy of this report, please contact Joe Dusek, water treatment plant supervisor, at 952-294-5902.

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 in 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 2021. 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.

Regulated Substances

Lead and Copper (Tested at Customer Taps)

Contaminant (date, if sampled in previous year)	MCLG	EPA AL	90% of Results Were Less Than	Homes with High Levels	Typical Sources
Lead (9/11/19)	0	90% of homes less than 15 ppb	<0.5 ppb	0 out of 30	Corrosion of household plumbing
Copper (9/11/19)	0	90% of homes less than 1.3 ppm	0.1 ppb	0 out of 30	Corrosion of household plumbing

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 MDH's website.

Inorganic and Organic Contaminants (Tested in Drinking Water)

Contaminant (date, if sampled in previous year)	MCLG	MCL	Highest Average or Highest Single Test Result	Range	Typical Sources
Barium (7/27/20)	2 ppm	2 ppm	0.03 ppm	N/A	Discharge of drilling wastes; discharge from metal refineries; erosion of natural deposit.
Cis-1,2- Dichloroethene (cis-1,2-dichloroethylene)	70 ppb	70 ppb	0.65 ppb	N/A	Discharge from chemical and agricultural chemical factories.

Contaminants Related to Disinfection (Tested in Drinking Water)

Substance (date, if sampled in previous year)	MCLG	MCL	Highest Average or Highest Single Test Result	Range	Typical Sources
Total Trihalomethanes (TTHMs)	N/A	80 ppb	34.6 ppb	25.70–34.60 ppb	Byproduct of drinking water disinfection.
Total Haloacetic Acids (HAA)*	N/A	60 ppb	8.1 ppb	5.70–8.10 ppb	Byproduct of drinking water disinfection.
Total Chlorine	4 ppm	4 ppm	1.03 ppm	0.92–1.14 ppm	Water additive used to control microbes.

*Total HAA refers to HAA5

Other Substances (Tested in Drinking Water)

Substance (date, if sampled in previous year)	MCLG	MCL	Highest Average or Highest Single Test Result	Range	Typical Sources
Flouride	4 ppm	4 ppm	0.63 ppm	0.53–0.67 ppm	Erosion of natural deposits; water additive to promote strong teeth.

Fluoride is nature's cavity fighter, with small amounts present naturally in many drinking water sources. There is an overwhelming of scientific evidence that fluoridation reduces tooth decay and cavities in children and adults, even when there is availability of fluoride from other sources, such as fluoride toothpaste and mouth rinses. Since studies show that optimal fluoride levels in drinking water benefit public health, municipal community water systems adjust the level of fluoride in the water to an optimal concentration between 0.5 to 0.9 parts per million (ppm) to protect your teeth. Fluoride levels below 2.0 ppm are not expected to increase the risk of a cosmetic condition known as enamel fluorosis.

Unregulated Substances

Unregulated contaminants do not have legal limits for drinking water.

Detection alone of a regulated or unregulated contaminant should not cause concern. The meaning of a detection should be determined considering current health effects information. We are often still learning about the health effects, so this information can change over time.

The following table shows the unregulated contaminants the City detected last year, as well as human-health based guidance values for comparison, where available. The comparison values are based only on potential health impacts and do not consider our ability to measure contaminants at very low concentrations or the cost and technology of prevention and/or treatment.

A person drinking water with a contaminant at or below the comparison value would be at little or no risk for harmful health effects. If the level of a contaminant is above the comparison value, people of a certain age or with special health conditions — like a fetus, infants, children, elderly, and people with impaired immunity — may need to take extra precautions. Because these contaminants are unregulated, EPA and MDH require no particular action based on detection of an unregulated contaminant.

Visit MDH's website to learn more about unregulated contaminants and the EPA's monitoring rule.

Unregulated Contaminants (Tested in Drinking Water)

Contaminant	Comparison Value	Highest Average Result or Highest Single Test Result	Range
Sodium*	20 ppm	11.4 ppm	N/A
Sulfate	500 ppm	22.7 ppm	N/A

*Home water softening can increase the level of sodium in your water.

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).

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).

Other Information

Educational Opportunities

Environmental Learning Center

The Eden Prairie Water Treatment Plant has an outstanding Environmental Learning Center and tours are offered for students wishing to learn more about public water systems. Learn more and schedule a tour.

Minnesota North College

Programs on Ely campus include a 60-credit-hour AAS in Water Quality Science as well as a 35-credit-hour diploma in Water Operations to prepare students for a career in either treatment or distribution operations with any public works department in the country. Learn more about this program or call 888-223-8068.

St. Cloud Technical and Community College

SCTCC's Water Environment Technologies Training 10-month certificate program or 14-month associates degree program provide students with the skills for jobs in drinking and wastewater treatment, as well as water and sewer maintenance. Learn more about this program or call 320-308-5952.

Water Softening

The City of Eden Prairie uses a lime-softening water treatment process that removes most of the calcium and magnesium from the water, resulting in softened water. Raw water drawn from the aquifer has a total hardness of 380 parts per million (ppm). After the water travels through the lime-softening plant, the total hardness is reduced to 90 ppm.

Some of the benefits Eden Prairie residents receive from softened water include:

Increased efficiency for soaps and detergents
Reduction in mineral staining on fixtures
Softer skin and clean, smooth hair
Fabrics that are softer, last longer and stay whiter
Increased lifespan of water appliances such as ice makers, dishwashers, water heaters and clothes washers
No need to maintain your own water softener
No salt brine discharge to the wastewater system, minimizing impacts to the environment