Helena Water System
EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the Montana Department of Environmental Quality, as well as information from the U.S. EPA Enforcement and Compliance History database (ECHO). For the latest quarter assessed by the U.S. EPA (January 2021 - March 2021), tap water provided by this water utility was in compliance with federal health-based drinking water standards.
Utility Details
- Helena, Montana
- Serves: 31,005
- Data available: 2013-2020*
- Source: Surface water
* 2013 testing is for chemicals in EPA's Third Unregulated Contaminant Monitoring Rule (UCMR-3) only. 2020/2021 testing is for chemicals in EPA's Fourth Unregulated Contaminant Monitoring Rule (UCMR-4) only.
Contaminants Detected
15
EXCEED
EWG HEALTH
GUIDELINES
28 Total Contaminants
- Legal does not necessarily equal safe. Getting a passing grade from the federal government does not mean the water meets the latest health guidelines.
- Legal limits for contaminants in tap water have not been updated in almost 20 years.
- The best way to ensure clean tap water is to keep pollution out of source water in the first place.
Looking for a countertop water filter?
Find out which filters earned EWG's recommendation
See the guideContaminants Detected
Arsenic
Potential Effect: cancer1,614x EWG'S HEALTH GUIDELINEArsenic
more aboutthis contaminant
Arsenic is a potent carcinogen and common contaminant in drinking water. Arsenic causes thousands of cases of cancer each year in the U.S. Click here to read more about arsenic.
Arsenic was found at 1,614 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.004 ppb for arsenic was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources
Agriculture
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Bromochloroacetic acid
Potential Effect: 106x EWG'S HEALTH GUIDELINEBromochloroacetic acid
more aboutthis contaminant
Bromochloroacetic acid is formed when chlorine or other disinfectants are used to treat drinking water. Bromochloroacetic acid and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy.
Bromochloroacetic acid was found at 106 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.02 ppb for bromochloroacetic acid was defined in a peer-reviewed scientific study by EWG and represents a on-in-a-million lifetime cancer risk level. This health guideline protects against cancer.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Bromodichloromethane
Potential Effect: cancer91x EWG'S HEALTH GUIDELINEBromodichloromethane
more aboutthis contaminant
Bromodichloromethane, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Bromodichloromethane and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
Bromodichloromethane was found at 91 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.06 ppb for bromodichloromethane was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Cadmium
Potential Effect: harm to the kidney17x EWG'S HEALTH GUIDELINECadmium
more aboutthis contaminant
Cadmium is a toxic metal found in food and drinking water. It has been linked to kidney toxicity, bone damage, cancer, and damage to developing fetuses.
Cadmium was found at 17 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.04 ppb for cadmium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to internal organs.
Pollution Sources
Industry
Runoff & Sprawl
Naturally Occurring
Filtering Options
Activated Carbon
Reverse Osmosis
Ion Exchange
Chloroform
Potential Effect: cancer92x EWG'S HEALTH GUIDELINEChloroform
more aboutthis contaminant
Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy.
Chloroform was found at 92 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Chromium (hexavalent)
Potential Effect: cancer2.1x EWG'S HEALTH GUIDELINEChromium (hexavalent)
more aboutthis contaminant
Chromium (hexavalent) is a carcinogen that commonly contaminates American drinking water. Chromium (hexavalent) in drinking water may be due to industrial pollution or natural occurrences in mineral deposits and groundwater. Read more about chromium (hexavalent).
Chromium (hexavalent) was found at 2.1 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.02 ppb for chromium (hexavalent) was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
Pollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Dibromoacetic acid
Potential Effect: 4.7x EWG'S HEALTH GUIDELINEDibromoacetic acid
more aboutthis contaminant
Dibromoacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
Dibromoacetic acid was found at 4.7 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.04 ppb for dibromoacetic acid was defined in a peer-reviewed scientific study by EWG and represents a on-in-a-million lifetime cancer risk level. This health guideline protects against cancer.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Dibromochloromethane
Potential Effect: cancer8.4x EWG'S HEALTH GUIDELINEDibromochloromethane
more aboutthis contaminant
Dibromochloromethane, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Dibromochloromethane and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
Dibromochloromethane was found at 8.4 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.1 ppb for dibromochloromethane was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Dichloroacetic acid
Potential Effect: cancer81x EWG'S HEALTH GUIDELINEDichloroacetic acid
more aboutthis contaminant
Dichloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
Dichloroacetic acid was found at 81 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.2 ppb for dichloroacetic acid was proposed in 2020 by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk.a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Haloacetic acids (HAA5)†
Potential Effect: cancer390x EWG'S HEALTH GUIDELINEHaloacetic acids (HAA5)
more aboutthis contaminant
Haloacetic acids are formed when disinfectants such as chlorine are added to tap water. The group of five haloacetic acids regulated by federal standards includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid.
Haloacetic acids (HAA5) was found at 390 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.1 ppb for the group of five haloacetic acids, or HAA5, was defined in a peer-reviewed scientific study by EWG and represents a one-in-a-million lifetime cancer risk level. This health guideline protects against cancer.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Haloacetic acids (HAA9)†
Potential Effect: cancer736x EWG'S HEALTH GUIDELINEHaloacetic acids (HAA9)
more aboutthis contaminant
Haloacetic acids are formed when disinfectants such as chlorine are added to tap water. The group of nine haloacetic acids includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid, which are regulated as a group by the federal government (HAA5); and bromochloroacetic acid, bromodichloroacetic acid, chlorodibromoacetic acid, and tribromoacetic acid.
Haloacetic acids (HAA9) was found at 736 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.06 ppb for the group of nine haloacetic acids, or HAA9, was defined in a peer-reviewed scientific study by EWG and represents a one-in-a-million lifetime cancer risk level as . This health guideline protects against cancer.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Nitrate and nitrite
Potential Effect: cancer3.1x EWG'S HEALTH GUIDELINENitrate and nitrite
more aboutthis contaminant
Nitrate and nitrite enter water from fertilizer runoff, septic tanks and urban runoff. These contaminants can cause oxygen deprivation for infants and increase the risk of cancer. Nitrite is significantly more toxic than nitrate. Click here to read more about nitrate.
Nitrate and nitrite was found at 3.1 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppm = parts per million
Health Risks
The health guideline of 0.14 parts per million, or ppm, for nitrate and nitrite is based on the equivalent health guideline for nitrate, as defined in a peer-reviewed scientific study by EWG. This guideline represents a one-in-one-million annual cancer risk level.Pollution Sources
Agriculture
Runoff & Sprawl
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Total trihalomethanes (TTHMs)†
Potential Effect: cancer286x EWG'S HEALTH GUIDELINETotal trihalomethanes (TTHMs)
more aboutthis contaminant
Trihalomethanes are cancer-causing contaminants that form during water treatment with chlorine and other disinfectants. The total trihalomethanes group includes four chemicals: chloroform, bromodichloromethane, dibromochloromethane and bromoform.
Total trihalomethanes (TTHMs) was found at 286 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The health guideline of 0.15 parts per billion, or ppb, for the group of four trihalomethanes, or THM4/TTHM, was defined in a peer-reviewed scientific study by EWG and represents a one-in-one-million lifetime cancer risk level.Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Trichloroacetic acid
Potential Effect: cancer200x EWG'S HEALTH GUIDELINETrichloroacetic acid
more aboutthis contaminant
Trichloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
Trichloroacetic acid was found at 200 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.1 ppb for trichloroacetic acid was proposed in 2020 by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk.a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Uranium
Potential Effect: cancer2.6x EWG'S HEALTH GUIDELINEUranium
more aboutthis contaminant
Uranium is a known human carcinogen. The federal legal limit for uranium is set at 30 micrograms per liter (corresponding to parts per billion), but utilities can also report uranium in picocuries per liter (pCi/L), which is a measure of radioactivity in water. EWG translated all uranium results to pCi/L using a conversion factor developed by the EPA. With this conversion approach, the limit of 30 ppb corresponds to 20 pCi/L. Drinking water with this much uranium would cause more than 4.6 cancer cases in a population of 100,000. California set a public health goal for uranium of 0.43 pCi/L.
Uranium was found at 2.6 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
pCi/L = picocuries per liter
Health Risks
The EWG Health Guideline of 0.43 pCi/L for uranium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. Three most common uranium isotopes are U-234, U-235 and U-238. All isotopes of uranium are radioactive, and the total radioactivity depends on the ratio of isotopes. This health guideline protects against cancer.
Pollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Includes chemicals detected in 2017-2019 for which annual utility averages exceeded an EWG-selected health guideline established by a federal or state public health authority; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 3) program in 2013 to 2015 (and subsequent testing when available), for which annual utility averages exceeded a health guideline established by a federal or state public health authority; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 4) program in 2017 to 2020 (and subsequent testing when available), for which annual utility averages exceeded a health guideline established by a federal or state public health authority; radiological contaminants detected between 2014 and 2019.
† HAA5 is a contaminant group that includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid. HAA9 is a contaminant group that includes the chemicals in HAA5 and bromochloroacetic acid, bromodichloroacetic acid, chlorodibromoacetic acid and tribromoacetic acid. TTHM is a contaminant group that includes bromodichloromethane, bromoform, chloroform and dibromochloromethane.
1,4-Dioxane
more aboutthis contaminant
1,4-Dioxane is a solvent classified by the EPA as a likely human carcinogen. It contaminates groundwater in many states due to industrial wastewater discharges, plastic manufacturing runoff and landfill runoff.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 0.35 ppb for 1,4-dioxane was defined by the Environmental Protection Agency as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.
Pollution Sources
Industry
Runoff & Sprawl
Filtering Options
Reverse Osmosis
Chlorate
more aboutthis contaminant
Chlorate forms in drinking water as a byproduct of disinfection. Chlorate impairs thyroid function, making chlorate exposure most harmful during pregnancy and childhood.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 210 ppb for chlorate was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against hormone disruption.
Pollution Sources
Agriculture
Industry
Treatment Byproducts
Chromium (total)
more aboutthis contaminant
Chromium is a naturally occurring metal, but industrial uses can elevate its levels in water. One form, hexavalent chromium, causes cancer. Total chromium is not a good indicator of the amount of hexavalent chromium in drinking water.
How your levels compare
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Pollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Fluoride
more aboutthis contaminant
Fluoride occurs naturally in surface and groundwater and is also added to drinking water by many water systems.
How your levels compare
This Utility
Legal Limit
National Average
State Average
ppm = parts per million
Pollution Sources
Treatment Byproducts
Filtering Options
Reverse Osmosis
Germanium
more aboutthis contaminant
Germanium is a naturally occuring element used as a component in semiconductors and fiber optics. Excessive exposures to germanium may harm the kidneys.
How your levels compare
This Utility
National Average
State Average
ppb = parts per billion
Pollution Sources
Naturally Occurring
Filtering Options
Reverse Osmosis
Manganese
more aboutthis contaminant
Manganese is a naturally occurring element that is common in food and drinking water. Excessive manganese exposures may impair children's attention, memory and intellectual capacity. Click here to read more about manganese.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 100 ppb for manganese was defined by the state of Minnesota as a health risk limit, the concentration of a contaminant that can be consumed with little or no risk to health. This health guideline protects against harm to the brain and nervous system.
Pollution Sources
Industry
Naturally Occurring
Filtering Options
Ion Exchange
Molybdenum
more aboutthis contaminant
Molybdenum is a metal that occurs naturally in soil, minerals and water. People who ingest large amounts can have increased levels of uric acid and gout-like symptoms.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 40 ppb for molybdenum was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against metabolic changes and excess formation of uric acid in the blood.
Pollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Monobromoacetic acid
more aboutthis contaminant
Monobromoacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 25 ppb for monobromoacetic acid was proposed in 2020 by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk.. This health guideline protects against muscular degeneration.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Monochloroacetic acid
more aboutthis contaminant
Monochloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 53 ppb for monochloroacetic acid was proposed in 2020 by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk.. This health guideline protects against system toxicity.
Pollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Radium, combined (-226 & -228)
Radium, combined (-226 & -228)
more aboutthis contaminant
Radium is a radioactive element that causes bone cancer and other cancers. It can occur naturally in groundwater, and oil and gas extraction activities such as hydraulic fracturing can elevate concentrations.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
pCi/L = picocuries per liter
Health Risks
EWG applied the health guideline of 0.05 pCi/L, defined by the California Office of Environmental Health Hazard Assessment as a public health goal for radium-226, to radium-226 and radium-228 combined. This health guideline protects against cancer.Pollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
Strontium
more aboutthis contaminant
Strontium is a metal that accumulates in the bones. Radioactive strontium-90 can cause bone cancer and leukemia, and any form of strontium at high doses can harm bone health.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 1,500 ppb for strontium was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against harm to bones.
Pollution Sources
Industry
Naturally Occurring
Filtering Options
Reverse Osmosis
Ion Exchange
trans-1,2-Dichloroethylene
trans-1,2-Dichloroethylene
more aboutthis contaminant
1,2-Dichloroethylene, a neurotoxic solvent, exists in two different forms: trans-1,2-dichloroethylene and cis-1,2-dichloroethylene. A mixture of the two forms is used to manufacture other solvents and chemical products.
How your levels compare
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 60 ppb for trans-1,2-dichloroethylene was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to internal organs.
Pollution Sources
Industry
Filtering Options
Activated Carbon
Reverse Osmosis
Vanadium
more aboutthis contaminant
Vanadium is a metal used in steels and other alloys. People are commonly exposed to vanadium in water and food. Excessive exposure can be toxic during pregnancy and childhood.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
ppb = parts per billion
Health Risks
The EWG Health Guideline of 21 ppb for vanadium was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against change in blood chemistry.
Pollution Sources
Industry
Naturally Occurring
Filtering Options
Ion Exchange
Includes chemicals detected in 2017-2019 for which annual utility averages were lower than an EWG-selected health guideline established by a federal or state public health authority; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 3) program in 2013 to 2015 (and subsequent testing when available), for which annual utility averages were lower than an EWG-selected health guideline established by a federal or state public health authority.
Other Contaminants Tested
✕Helena Water System compliance with legally mandated federal standards:
- From April 2019 to March 2021, Helena Water System complied with health-based drinking water standards.
Information in this section on Helena Water System comes from the U.S. EPA Enforcement and Compliance History Online database (ECHO).
LEARN MORE ABOUT THIS UTILITYWater Filters That Can Reduce Contaminant Levels
| Contaminant | Activated Carbon | Reverse Osmosis | Ion Exchange |
| CONTAMINANTS ABOVE HEALTH GUIDELINES | |||
| Arsenic | ✔ | ✔ | |
| Bromochloroacetic acid | ✔ | ✔ | |
| Bromodichloromethane | ✔ | ✔ | |
| Cadmium | ✔ | ✔ | ✔ |
| Chloroform | ✔ | ✔ | |
| Chromium (hexavalent) | ✔ | ✔ | |
| Dibromoacetic acid | ✔ | ✔ | |
| Dibromochloromethane | ✔ | ✔ | |
| Dichloroacetic acid | ✔ | ✔ | |
| Haloacetic acids (HAA5) | ✔ | ✔ | |
| Haloacetic acids (HAA9) | ✔ | ✔ | |
| Nitrate & nitrite | ✔ | ✔ | |
| Total trihalomethanes (TTHMs) | ✔ | ✔ | |
| Trichloroacetic acid | ✔ | ✔ | |
| Uranium, combined (pCi/L) | ✔ | ✔ | |
| OTHER CONTAMINANTS DETECTED | |||
| 1,4-Dioxane | ✔ | ||
| Chlorate | |||
| Chromium (total) | ✔ | ✔ | |
| Fluoride | ✔ | ||
| Germanium | ✔ | ||
| Manganese | ✔ | ||
| Molybdenum | ✔ | ✔ | |
| Monobromoacetic acid | ✔ | ✔ | |
| Monochloroacetic acid | ✔ | ✔ | |
| Radium, combined (-226 & -228) | ✔ | ✔ | |
| Strontium | ✔ | ✔ | |
| trans-1,2-Dichloroethylene | ✔ | ✔ | |
| Vanadium | ✔ | ||
Take Action
Contact Your Local Official
One of the best ways to push for cleaner water is to hold accountable the elected officials who have a say in water quality – from city hall and the state legislature to Congress all the way to the Oval Office – by asking questions and demanding answers.
LEARN MOREFilter Out Contaminants
Check out our recommendations for filters to protect your water against the detected contaminants.
EWG’S WATER FILTER GUIDE
