Drinking Water

Drinking Water Sources

Your drinking water comes from a groundwater source. The City of North St. Paul has five wells ranging from 458 to 531 feet deep that draw water from the Prairie Du Chien-Jordan and Jordan aquifers.

Download the City of North St. Paul's 2021 Drinking Water Report (pdf)

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 percent 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 percent of Minnesota's drinking water.

The Minnesota Department of Health (MDH) provides information about your drinking water source in a water assessment, including:

  • How North St. Paul is protecting your drinking water source
  • Nearby threats to your drinking water source
  • How easily water and pollution can move from the surface of the land into drinking water sources, based on natural geology and the way wells are constructed.

Call 651-201-4700 or 800-818-9318 between 8:00 a.m. and 4:30 p.m. Monday through Friday for your source water assessment 


Contaminants can get into 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 from 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 Minnesota Department of Health provides information about your drinking water source(s) in a source water assessment, including:

  • How North Saint Paul is protecting your drinking water source(s);
  • Nearby threats to your drinking water sources;
  • How easily water and pollution can move from the surface of the land into drinking water sources, based on natural geology and the way wells are constructed.

Find your source water assessment at Source Water Assessments or call 651-201-4700 between 8:00 a.m. and 4:30 p.m., Monday through Friday.

Drinking Water Standards

The US Environmental Protection Agency (EPA) sets safe drinking water standards. These standards limit the amount of specific contaminants allowed in drinking water. This ensures that tap water is safe to drink for most people. The US Food and Drug Administration regulates the amount of certain contaminants in bottled water. Bottled water must provide the same public health protection as public tap water.

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 the 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

North St. Paul Monitoring Results

We work with the Minnesota Department of Health (MDH) to test drinking water for more than 100 contaminants. It is not unusual to detect contaminants in small amounts. No water supply is ever completely free of contaminants. Drinking water standards protect Minnesotans from substances that may be harmful to their health.

Helpful Resources on the Monitoring and Testing of Drinking Water in Minnesota

Basics of Monitoring and Testing of Drinking Water in Minnesota

How to Read the Water Quality Data Tables

The tables below show the contaminants we found last year or the most recent time we sampled for that contaminant. They also show the levels of those contaminants and the Environmental Protection Agency’s limits. Substances that we tested for but did not find are not included in the tables.

We sample for some contaminants less than once a year because their levels in water are not expected to change from year to year. If we found any of these contaminants the last time we sampled for them, we included them in the tables below with the detection date.

We 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 651-201-4700 or 1-800-818-9318 between 8:00 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 when 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.


  • AL (Action Level): The concentration of a contaminant which, if exceeded, triggers treatment or other requirements that a water system must follow. EPA: Environmental Protection Agency
  • 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.
  • N/A (Not applicable): Does not apply.
  • pCi/l (picocuries per liter): A measure of radioactivity.
  • ppb (parts per billion): One part per billion in water is like one drop in one billion drops of water or about one drop in a swimming pool. ppb is the same as micrograms per liter (μg/l).
  • ppm (parts per million): One part per million is like one drop in one million drops of water or about one cup in a swimming pool. ppm is the same as milligrams per liter (mg/l).
  • PWSID: Public water system identification.

Monitoring Results—Regulated Substances 2021

Lead and Copper-Tested at customer tap

Date if sampled in previous year)
Ideal Goal (MCLG)
Action Level
90% of Results
Were Less Than
Number of Homes 
with High Levels
Violation Typical 
Lead (08/14/19) 0 ppb 90% of homes 
less than 15 ppb
3.7 ppb 1 out of 31 NO Corrosion of household plumbing

Copper (09/14/19) 0 ppm 90% of homes less than 15 ppb 0.16 ppm 0 out of 31 No Corrosion of household plumbing

Inorganic & Organic Contaminants -Tested in drinking water

(Date, if sampled in previous year)
EPA's Ideal Goal
EPA's Limit
Average or 
Highest Single Test Result
Range of Detected 
Test Results
Violation Typical  

Nitrate 10 ppm    10.4 ppm  0.78 ppm 0.00-0.78 ppm NO Runoff from fertilizer use; 
Leaching from septic tanks, 
sewage; Erosion of natural deposits
Barium 2 ppm 2 ppm 0.03 ppm 0.000-0.0316 ppm No Discharge of drilling wastes; Discharge from metal refineries; Erosion of natural deposit
Combined Radium (2020 0 pCi/l 5.4 pCi/l 3.1 pCi/l N/A No Erosion of natural deposits

Other Substances - Tested in drinking water

 (Date, if sampled in previous year)
EPA's Ideal Goal
EPA's Limit

Highest Average or
Highest Single 
Test Result
Range of Detected 
Test Results
Violation Typical Sources
Fluoride 4.0 ppm 4.0 ppm 1.06 ppm 0.79-1.10 ppm No Erosion of natural deposits; Water additive to promote strong teeth.

Monitoring Results—Unregulated Substances

In addition to testing drinking water for contaminants regulated under the Safe Drinking Water Act, we sometimes also monitor for contaminants that are not regulated. 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 we 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. They may be set at levels that are costly, challenging, or impossible for water systems to meet (for example, large-scale treatment technology may not exist for a given contaminant).

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. We are notifying you of the unregulated contaminants we have detected as a public education opportunity.

Unregulated Contaminants - Tested in drinking water

Contaminant Comparison Value Highest Average Result or 
Highest Single Test Result
Range of Detected 
Test Results
Sodium* 20 ppm 8.96 ppm 4.37-8,86 ppm
Sulfate 500 ppm 12 ppm 8.34-12.00 ppm

*Note that home water softening can increase the level of sodium in your water.

Some People Are More Vulnerable to Contaminants in Drinking Water

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 to contaminants in drinking water. These people or their caregivers should seek advice about drinking water from their health care providers. EPA/Centers for Disease Control (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.

Lead in Drinking Water

You may be in contact with lead through paint, water, dust, soil, food, hobbies, or your job. Coming in contact with lead can cause serious health problems for everyone. There is no safe level of lead. Babies, children under six years, and pregnant women are at the highest risk.

Lead is rarely in a drinking water source, but it can get in your drinking water as it passes through lead service lines and your household plumbing system. North Saint Paul is responsible for providing high quality drinking water, but it cannot control the plumbing materials used in private buildings.

Read below to learn how you can protect yourself from lead in drinking water.

  1. Let the water run for 30-60 seconds before using it for drinking or cooking if the water has not been turned on in over six hours. If you have a lead service line, you may need to let the water run longer. A service line is the underground pipe that brings water from the main water pipe under the street to your home. 
    • You can find out if you have a lead service line by contacting your public water system, or you can check by following the steps at: https://www.mprnews.org/story/2016/06/24/npr-find-lead-pipes-in-your-home
    • The only way to know if lead has been reduced by letting it run is to check with a test. If letting the water run does not reduce lead, consider other options to reduce your exposure.
  2. Use cold water for drinking, making food, and making baby formula. Hot water releases more lead from pipes than cold water.
  3. Test your water. In most cases, letting the water run and using cold water for drinking and cooking should keep lead levels low in your drinking water. If you are still concerned about lead, arrange with a laboratory to test your tap water. Testing your water is important if young children or pregnant women drink your tap water.
  4. Treat your water if a test shows your water has high levels of lead after you let the water run.

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