The Idaho Department of Health and Welfare created the interactive map below to make private well owners aware of existing ground water quality data in their area and promote regular ground water quality testing. Ground water quality at privately owned wells is not regulated by the State of Idaho. Private well owners are responsible for maintaining their well and ensuring the water is safe to drink, which can be accomplished through periodic testing.
View the map here
About the Map
Private wells displayed on the map were sampled by the Idaho Department of Water Resources , the Idaho Department of Environmental Quality , the Idaho State Department of Agriculture , and private well owners between 2004-2020. Each well contains the most recent sampling results for up to nine chemicals, the year it was sampled, the sampling agency, and the well depth if it is known.
Agencies may have additional data that has not been included as part of this map. Additionally, more recent data may exist for certain chemicals that were unavailable at the time this map was published. Contact the individual sampling agencies for more information.
Find a location and set your search radius
Enter an address or place of interest in the search field in the panel to the left of the map. The map will default to locating wells within a two mile radius of your location. Use the text box or slider to expand the search radius in miles. Alternatively, click the set location icon , located next to the magnifying glass icon, and click on the map to set a location if the address is unknown.
View results
Wells found within the designated search radius are listed below the slider. Wells over a primary drinking water standard are titled as Primary Standard Exceeded. Click on individual search results, or click directly on a well symbol to see the data.
Note multiple agencies may have sampled the same well, but assigned a different site ID. Additionally, the same agency may have sampled the same well for different chemicals in different years. Use the arrow in the pop up window after clicking on a well to view all available data.
Drinking Water Standards
Primary
Arsenic, fluoride, nitrate, selenium, and uranium have primary drinking water standards. Public drinking water systems are regulated by DEQ and are required to comply with these, and other standards not represented here, to protect human health. The units of measure (e.g., ug/L or mg/L) provided in the following table may not match the units of measure on the laboratory report provided to you. If this is the case, results will need to be converted to make the best use of this table. If you need assistance converting or interpreting results, call the laboratory that did the analysis or IDHW's Environmental Health Hotline at 1-800-445-8647 or radon@dhw.idaho.gov.
Chemical
|
Primary Standard
|
Health Effects
|
| Arsenic |
10 ug/L |
Long term exposure to arsenic from drinking water can cause cancer and skin lesions. |
| Fluoride |
4 mg/L |
Depending on the length and amount of exposure, fluoride can stain teeth, increase risk of broken bones, or cause pain and tenderness in joints and bones. |
| Nitrate |
10 mg/L |
Nitrate can be converted to nitrite in humans where it lessens the ability of blood to carry oxygen. This is of greatest concern for infants, pregnant, and nursing women. |
| Selenium |
0.05 mg/L |
Prolonged exposure to elevated levels of selenium can cause fingernail or hair loss, numbness in extremities or circulation problems. |
| Uranium |
30 ug/L |
The greatest risk is kidney damage, especially for young children because their bodies are still developing. |
| Bacteria* |
ZERO |
Most coliform bacteria do not cause disease, but they can indicate the presence of other harmful bacteria such as Escherichia coli (E. coli). E. coli can cause nausea, vomiting, fever, and diarrhea.
* Monitoring results related to bacteria were not included in this map because the presence of bacteria is typically a result of site specific conditions rather than a wide scale problem.
|
Secondary
Chloride, fluoride, iron, manganese, and sulfate have secondary drinking water standards. These guidelines were established by EPA to manage aesthetic considerations of drinking water such as taste, color and odor. These contaminants are not considered to present a risk to human health at the secondary levels.
Chemical
|
Secondary Standard
|
Health Effects
|
| Chloride |
250 mg/L |
Salty taste |
| Fluoride |
2 mg/L |
Tooth discoloration |
| Iron |
0.3 mg/L |
Rust color, sediment, metallic taste, reddish or orange staining |
| Manganese |
0.05 mg/L |
Black to brown color, black staining, or bitter metallic taste |
| Sulfate |
250 mg/L |
Salty taste |
Water Quality Testing
Water samples can be taken by homeowners and submitted to a laboratory for testing. Click here for a list of Idaho-certified laboratories . The laboratory, your DEQ regional office , or public health district can tell you how to obtain the necessary sample containers, how to take the sample, and how quickly you must get the sample to the laboratory. If you do not want to take the samples yourself, an environmental consultant can conduct the sampling for you.
Testing Frequency
Testing
|
Chemical
|
| Once a Year |
Bacteria, Nitrate |
| Once every 3-5 years |
Arsenic, Fluoride, Selenium, Uranium |
| If your water tastes, smells, or looks strange |
Chloride, Manganese, Sulfate |
| If you live in an agricultural area and/or have underground tanks with petroleum |
Pesticides, Petroleum |
| If you have a formula-fed infant under 6 months |
Manganese |
Fix a Problem
If there is a problem with your drinking water, you may need to disinfect your well, repair your system, find an alternative drinking water source, and/or install a water treatment device to remove contaminants. When installing a treatment system, look for NSF International certified treatment devices. You need more information on how to treat your water for contaminants? We have information for you here.
Treatment Resources
Protecting Your Wellhead
Well maintenance and managing potential sources of contamination are very important to keep your water safe.
Inspect the well and surrounding area regularly:
- Are the well casing, well cap, and surface seals intact and in good shape? Is the top of the well at least 18 inches above the ground?
- Is the area around the well sloped to drain surface water away from the well?
- Are irrigation valves set properly to prevent backflow?
Fertilizers, animal waste, pesticides, septic systems and other potential sources of contamination should be located and managed so they do not contaminate the well.
- Avoid mixing or using fertilizers, herbicides, fuels, motor oil, and other pollutants near the well.
- Do not pile snow, leaves, or other materials around the well.
- Take care when working around the well to avoid damaging the casing.
- Properly locate and manage septic systems.
Contribute Data
Private well owners utilizing the Idaho Bureau of Laboratories (IBL) as their testing laboratory have the opportunity to participate in citizen science by allowing their results to be displayed publicly on this map. Citizen science is the voluntary involvement of the public in scientific research, in this case data collection. This work helps professional scientists and other private well owners to better understand ground water quality in Idaho.
If you own a private well, consider becoming a citizen scientists by granting permission on IBL’s submission form to display your tests results on this map. There are more than 3,000 wells displayed on the map currently. Note data collected by citizen scientists may not have been collected under a Quality Assurance Project Plan (QAPP), a written document that outlines the procedures a monitoring project will use to ensure the samples collected are of high enough quality to meet project needs. Using a QAPP is not required to display your results, but resources are available online. Click here for more information.
