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EWG's Tap Water Database — 2021 UPDATE

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Roche Harbor Water System Inc.

EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the Washington State Department of Health, 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

  • San Juan County, Washington
  • Serves: 329
  • Data available: 2014-2019
  • Source: Surface water

Contaminants Detected

9

EXCEED
EWG HEALTH
GUIDELINES

15 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?

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Contaminants Detected

Bromochloroacetic acid

Potential Effect: 166x EWG'S HEALTH GUIDELINE
THIS UTILITY3.31 ppb
EWG HEALTH GUIDELINE0.02 ppb
NO LEGAL LIMIT
DETAILS
X

Bromochloroacetic acid

more about
this 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 166 times above EWG's Health Guideline.

EWG Health Guideline

0.02 ppb or less

This Utility

3.31 ppb

National Average

3.16 ppb

State Average

0.231 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Bromodichloromethane

Potential Effect: cancer184x EWG'S HEALTH GUIDELINE
THIS UTILITY11.1 ppb
EWG HEALTH GUIDELINE0.06 ppb
NO LEGAL LIMIT
DETAILS
X

Bromodichloromethane

more about
this 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 184 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

11.1 ppb

National Average

5.79 ppb

State Average

1.82 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Chloroform

Potential Effect: cancer49x EWG'S HEALTH GUIDELINE
THIS UTILITY19.6 ppb
EWG HEALTH GUIDELINE0.4 ppb
NO LEGAL LIMIT
DETAILS
X

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 49 times above EWG's Health Guideline.

EWG Health Guideline

0.4 ppb or less

This Utility

19.6 ppb

National Average

15.5 ppb

State Average

16 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Dibromoacetic acid

Potential Effect: 29x EWG'S HEALTH GUIDELINE
THIS UTILITY1.14 ppb
EWG HEALTH GUIDELINE0.04 ppb
NO LEGAL LIMIT
DETAILS
X

Dibromoacetic acid

more about
this 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 29 times above EWG's Health Guideline.

EWG Health Guideline

0.04 ppb or less

This Utility

1.14 ppb

National Average

1.1 ppb

State Average

0.116 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Dibromochloromethane

Potential Effect: cancer60x EWG'S HEALTH GUIDELINE
THIS UTILITY5.98 ppb
EWG HEALTH GUIDELINE0.1 ppb
NO LEGAL LIMIT
DETAILS
X

Dibromochloromethane

more about
this 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 60 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

5.98 ppb

National Average

3.29 ppb

State Average

0.634 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Dichloroacetic acid

Potential Effect: cancer34x EWG'S HEALTH GUIDELINE
THIS UTILITY6.87 ppb
EWG HEALTH GUIDELINE0.2 ppb
NO LEGAL LIMIT
DETAILS
X

Dichloroacetic acid

more about
this 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 34 times above EWG's Health Guideline.

EWG Health Guideline

0.2 ppb or less

This Utility

6.87 ppb

National Average

7.97 ppb

State Average

6.16 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Haloacetic acids (HAA5)†

Potential Effect: cancer143x EWG'S HEALTH GUIDELINE
THIS UTILITY14.3 ppb
EWG HEALTH GUIDELINE0.1 ppb
LEGAL LIMIT60 ppb
DETAILS
X

Haloacetic acids (HAA5)

more about
this 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 143 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

14.3 ppb

Legal Limit

60 ppb

National Average

17.1 ppb

State Average

15.3 ppb
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Total trihalomethanes (TTHMs)†

Potential Effect: cancer250x EWG'S HEALTH GUIDELINE
THIS UTILITY37.5 ppb
EWG HEALTH GUIDELINE0.15 ppb
LEGAL LIMIT80 ppb
DETAILS
X

Total trihalomethanes (TTHMs)

more about
this 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 250 times above EWG's Health Guideline.

EWG Health Guideline

0.15 ppb or less

This Utility

37.5 ppb

Legal Limit

80 ppb

National Average

29.7 ppb

State Average

19.2 ppb
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Trichloroacetic acid

Potential Effect: cancer62x EWG'S HEALTH GUIDELINE
THIS UTILITY6.22 ppb
EWG HEALTH GUIDELINE0.1 ppb
NO LEGAL LIMIT
DETAILS
X

Trichloroacetic acid

more about
this 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 62 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

6.22 ppb

National Average

6.62 ppb

State Average

8.76 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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

water treatment icon

Treatment Byproducts

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

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.



† 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 Contaminants Tested


Chemicals tested for but not detected from 2014 to 2019:

1,1,1,2-Tetrachloroethane , 1,1,1-Trichloroethane , 1,1,2,2-Tetrachloroethane , 1,1,2-Trichloroethane , 1,1-Dichloroethane , 1,1-Dichloroethylene , 1,1-Dichloropropene , 1,2,3-Trichlorobenzene , 1,2,3-Trichloropropane , 1,2,4-Trichlorobenzene , 1,2,4-Trimethylbenzene , 1,2-Dichloroethane , 1,2-Dichloropropane , 1,3,5-Trimethylbenzene , 1,3-Dichloropropane , 2,2-Dichloropropane , 2,4,5-T , 2,4-D , 2,4-DB , Acifluorfen (Blazer) , Antimony , Arsenic , Asbestos , Benzene , Benzoic acid , Beryllium , Bromobenzene , Bromochloromethane , Bromomethane , Cadmium , Carbon tetrachloride , Chloroethane , Chloromethane , Chromium (total) , cis-1,2-Dichloroethylene , cis-1,3-Dichloropropene , Cyanide , DCPA di-acid degradate , Dibromomethane , Dicamba , Dichlorodifluoromethane , Dichloromethane (methylene chloride) , Dinoseb , Ethylbenzene , Fluoride , Hexachlorobutadiene , Isopropylbenzene , m-Dichlorobenzene , Mercury (inorganic) , Monobromoacetic acid , Monochlorobenzene (chlorobenzene) , n-Butylbenzene , n-Propylbenzene , Naphthalene , Nitrate & nitrite , Nitrite , o-Chlorotoluene , o-Dichlorobenzene , p-Chlorotoluene , p-Dichlorobenzene , p-Isopropyltoluene , Pentachlorophenol , Picloram , Radium, combined (-226 & -228) , sec-Butylbenzene , Selenium , Silver , Styrene , tert-Butylbenzene , Tetrachloroethylene (perchloroethylene) , Thallium , Toluene , trans-1,2-Dichloroethylene , trans-1,3-Dichloropropene , Trichloroethylene , Trichlorofluoromethane , Vinyl chloride , Xylenes (total)

Roche Harbor Water System Inc. compliance with legally mandated federal standards:

  • From April 2019 to March 2021, Roche Harbor Water System Inc. complied with health-based drinking water standards.
  • 1 QUARTER
    in violation of any federal drinking water standard from April 2019 to March 2021

Information in this section on Roche Harbor Water System Inc. comes from the U.S. EPA Enforcement and Compliance History Online database (ECHO).

LEARN MORE ABOUT THIS UTILITY

Water Filters That Can Reduce Contaminant Levels

ContaminantActivated Carbonactivated carbonReverse Osmosisreverse osmosisIon Exchangeion exchange
CONTAMINANTS ABOVE
HEALTH GUIDELINES
Bromochloroacetic acid
Bromodichloromethane
Chloroform
Dibromoacetic acid
Dibromochloromethane
Dichloroacetic acid
Haloacetic acids (HAA5)
Total trihalomethanes (TTHMs)
Trichloroacetic acid
OTHER CONTAMINANTS
DETECTED
Barium
Bromoform
Dalapon
Manganese
Monochloroacetic acid
Nitrate

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 MORE

Filter Out Contaminants

Check out our recommendations for filters to protect your water against the detected contaminants.

EWG’S WATER FILTER GUIDE