Contaminants Detected
EXCEED GUIDELINES
Bromodichloromethane
Potential Effect: cancer

This Utility: 9.19 ppb
No Legal Limit
153x
EWG's Health Guideline: 0.06 ppb
Bromodichloromethane
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 153 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.06 ppb for bromodichloromethane was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Chloroform
Potential Effect: cancer

This Utility: 41.5 ppb
No Legal Limit
104x
EWG's Health Guideline: 0.4 ppb
Chloroform
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 104 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.4 ppb for chloroform was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Dibromoacetic acid
Potential Effect:

This Utility: 0.0833 ppb
No Legal Limit
2.8x
EWG's Health Guideline: 0.03 ppb
Dibromoacetic acid
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 2.8 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.03 ppb for dibromoacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Dibromochloromethane
Potential Effect: cancer

This Utility: 2.04 ppb
No Legal Limit
20x
EWG's Health Guideline: 0.1 ppb
Dibromochloromethane
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 20 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.1 ppb for dibromochloromethane was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Dichloroacetic acid
Potential Effect: cancer

This Utility: 10.3 ppb
No Legal Limit
52x
EWG's Health Guideline: 0.2 ppb
Dichloroacetic acid
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 52 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.2 ppb for dichloroacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to reproduction and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Haloacetic acids (HAA5)
Potential Effect: cancer

This Utility: 29.0 ppb
Legal Limit: 60 ppb
290x
EWG's Health Guideline: 0.1 ppb
Haloacetic acids (HAA5)
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 290 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
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.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Haloacetic acids (HAA9)
Potential Effect: cancer

This Utility: 39.7 ppb
No Legal Limit
662x
EWG's Health Guideline: 0.06 ppb
Haloacetic acids (HAA9)
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 662 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
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.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2018-2021.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluorooctanoic acid (PFOA)
Potential Effect: cancer

This Utility: 1.87 ppt
Proposed Legal Limit: 4 ppt
21x
EWG's Health Guideline: 0.09 ppt
Perfluorooctanoic acid (PFOA)
Perfluorooctanoic acid (PFOA) is a member of a group of perfluorinated chemicals used in many consumer products. PFOA and other perfluorinated chemicals can cause serious health effects, including cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes. These chemicals are persistent in the environment and they accumulate in people. Click here to read more about perfluorinated chemicals.
Perfluorooctanoic acid (PFOA) was found at 21 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Proposed Legal Limit
National Average
State Average
Health Risks
The EWG Health Guideline of 0.09 ppt for PFOA was was defined by EPA's final toxicity value from the Office of Water’s Final Human Health Toxicity Assessment. This health guideline protects againat cardiovascular harm and harm to fetal growth.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Total trihalomethanes (TTHMs)
Potential Effect: cancer

This Utility: 52.6 ppb
Legal Limit: 80 ppb
351x
EWG's Health Guideline: 0.15 ppb
Total trihalomethanes (TTHMs)
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 351 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
Legal Limit
National Average
State Average
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.
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Trichloroacetic acid
Potential Effect: cancer

This Utility: 17.6 ppb
No Legal Limit
176x
EWG's Health Guideline: 0.1 ppb
Trichloroacetic acid
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 176 times above EWG's Health Guideline.
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 0.1 ppb for trichloroacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to reproduction and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Includes chemicals detected in 2021-2023 for which annual utility averages exceeded an EWG-selected health guideline established by a federal or state public health authority.
† 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.
OTHER DETECTED
4-Androstene-3,17-dione

This Utility: 0.200 ppt
No Legal Limit
No EWG Health Guideline
4-Androstene-3,17-dione
Human sex hormones are sometimes detected at low concentrations in drinking water. There are no current health guidelines to determine whether these exposures are safe, or if they could pose a risk to human health.
How your levels compare
This Utility
National Average
State Average
EWG Health Guideline
Not yet determined
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2016.
ppt = parts per trillionPollution Sources
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Bromoform

This Utility: 0.0208 ppb
No Legal Limit
EWG's Health Guideline: 0.5 ppb
Bromoform
Bromoform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Bromoform 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
Health Risks
The EWG Health Guideline of 0.5 ppb for bromoform is based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer, harm to reproduction and child development, and change to fetal growth and development .
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Manganese

This Utility: 8.47 ppb
No Legal Limit
EWG's Health Guideline: 100 ppb
Manganese
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
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.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2023.
ppb = parts per billionPollution Sources
Industry
Naturally Occurring
Filtering Options
Ion Exchange
Monobromoacetic acid

This Utility: 0.0417 ppb
No Legal Limit
EWG's Health Guideline: 25 ppb
Monobromoacetic acid
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
Health Risks
The EWG Health Guideline of 25 ppb for monobromoacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against change to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Monochloroacetic acid

This Utility: 1.000 ppb
No Legal Limit
EWG's Health Guideline: 53 ppb
Monochloroacetic acid
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
Health Risks
The EWG Health Guideline of 53 ppb for monochloroacetic acid was defined by the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk.a public health goal. This health guideline protects against change to fetal growth and development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2021-2023.
ppb = parts per billionPollution Sources
Treatment Byproducts
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluorohexanoic Acid (PFHxA)

This Utility: 1.13 ppt
No Legal Limit
EWG's Health Guideline: 1,000 ppt
Perfluorohexanoic Acid (PFHxA)
Perfluorohexanoic acid is a member of a group of perfluorinated chemicals used in many consumer products. Perfluorinated chemicals can cause serious health effects, including cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes. These chemicals are persistent in the environment and they accumulate in people. Click here to read more about perfluorinated chemicals.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 1,000 ppt for perfluorohexanoic acid was defined by EPA's toxicity value published in the Integrated Risk Information System's toxicological review. This health guideline protects against harm to fetal growth and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2018-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Perfluoropentanoic Acid (PFPeA)

This Utility: 1.000 ppt
No Legal Limit
EWG's Health Guideline: 1,000 ppt
Perfluoropentanoic Acid (PFPeA)
Perfluoropentanoic Acid (PFPeA) is a member of a group of perfluorinated chemicals used in many consumer products. PFOS and other perfluorinated chemicals can cause serious health effects, including cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes. These chemicals are persistent in the environment and they accumulate in people. Click here to read more about perfluorinated chemicals.
How your levels compare
EWG Health Guideline
This Utility
National Average
State Average
Health Risks
The EWG Health Guideline of 1,000 ppt for PFPeA was defined by EPA's recommended application of the toxicity value for PFHxA published in the Integrated Risk Information System’s toxicological review. This health guideline protects against harm to fetal growth and child development.
Legal Limit
None
Understanding the Data
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2018-2024.
ppt = parts per trillionPollution Sources
Industry
Runoff & Sprawl
Filtering Options
Activated Carbon
Reverse Osmosis
Includes chemicals detected in 2021-2023 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
✕Chemicals tested for but not detected:
1-butanol, 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic aci, 17-beta-Estradiol, 2-methoxyethanol, 2-propen-1-ol, 4,8-dioxa-3H-perfluorononanoic acid (ADONA), 4:2 Fluorotelomer Sulfonic Acid (4:2 FTSA), 6:2 Fluorotelomer Sulfonic Acid (6:2 FTSA), 8:2 Fluorotelomer Sulfonic Acid (8:2 FTSA), 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (, Alpha-hexachlorocyclohexane, Asbestos, Butanoic acid, 2,2,3,3,4,4-hexafluoro-4-(trifluoro, Butylated hydroxyanisole, Chlorpyriphos, Dimethipin, Equilin, Estriol, Estrone, Ethinyl estradiol, Ethoprop, Germanium, Hexafluoropropylene oxide dimer acid (HFPO-DA), Lithium, N-ethyl perfluorooctane sulfonamido acetic acid (N, N-methyl perfluorooctanesulfonamidoacetic acid, Nonafluoro-3,6-dioxaheptanoic acid, o-toluidine, Oxyflurofen, Perfluoro(2-ethoxyethane)sulfonic acid, Perfluorobutane sulfonate (PFBS), Perfluorobutanoic acid (PFBA), Perfluorodecanoic acid (PFDA), Perfluorododecanoic acid (PFDoA), Perfluoroheptane sulfonic acid (PFHpS), Perfluoroheptanoic acid (PFHPA), Perfluorohexane sulfonate (PFHXS), Perfluorononanoic acid (PFNA), Perfluorooctane sulfonate (PFOS), Perfluoropentane sulfonic acid (PFPeS), Perfluorotetradecanoic acid (PFTA), Perfluorotridecanoic acid (PFTrDA), Perfluoroundecanoic acid (PFUnA), Permethrin, Profenofos, Propanoic acid, 2,2,3,3-tetrafluoro-3-(trifluorome, Quinoline, Tebuconazole, Testosterone, Tribufos
Find A Filter
Utility:
Aquarion Water Company of Connecticut - Canaan SysCarbon Filters
FILTERS 10 contaminants exceeding guidelines (+6 others)
Can reduce the levels of many common contaminants.
pros
- Lower upfront cost
- Reduced maintenance
cons
- Does not remove all contaminants
Reverse Osmosis
FILTERS 10 contaminants exceeding guidelines (+6 others)
Can reduce the levels of many common contaminants.
pros
- Most effective
cons
- Higher upfront cost
- Requires more maintenance
- Wastes water
Other Considerations
Ion Exchange
Pros: Softens hard water, Reduces some contaminants
Cons: Doesn’t remove all contaminants
Whole-House Filters
Pros: Useful for reducing radiologicals and TCE
Cons: Expensive to install and maintain, Risk of bacterial contamination
Distillation
Pros: Removes heavy metals and harmful microbes
Cons: Does not reduce most contaminants
Explore filter options for each contaminant. See which technologies are effective at reducing specific contaminants to help you make an informed decision on the best water treatment solution for your needs.
CONTAMINANTS ABOVE HEALTH GUIDELINES | activated carbon | reverse osmosis | ion exchange |
Bromodichloromethane | |||
Chloroform | |||
Dibromoacetic acid | |||
Dibromochloromethane | |||
Dichloroacetic acid | |||
Haloacetic acids (HAA5) | |||
Haloacetic acids (HAA9) | |||
Perfluorooctanoic acid (PFOA) | |||
Total trihalomethanes (TTHMs) | |||
Trichloroacetic acid | |||
OTHER CONTAMINANTS DETECTED | activated carbon | reverse osmosis | ion exchange |
4-Androstene-3,17-dione | |||
Bromoform | |||
Manganese | |||
Monobromoacetic acid | |||
Monochloroacetic acid | |||
Perfluorohexanoic Acid (PFHxA) | |||
Perfluoropentanoic acid (PFPeA) |