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EWG's Tap Water Database — 2021 UPDATE

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Wahiawa

EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the Hawaii 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

  • Honolulu County, Hawaii
  • Serves: 23,348
  • Data available: 2013-2019*
  • Source: Groundwater

    • * 2013 testing is for chemicals in EPA's Third Unregulated Contaminant Monitoring Rule (UCMR-3) only.

Contaminants Detected

7

EXCEED
EWG HEALTH
GUIDELINES

16 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.

What To Do

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Contaminants Detected

VIEW: EXCEED GUIDELINES OTHER DETECTED

1,2,3-Trichloropropane

Potential Effect: cancer102x EWG'S HEALTH GUIDELINE
THIS UTILITY0.0715 ppb
EWG HEALTH GUIDELINE0.0007 ppb
NO LEGAL LIMIT
DETAILS
X

1,2,3-Trichloropropane

more about
this contaminant

1,2,3-Trichloropropane is a potent carcinogen that contaminates drinking water in agricultural regions where it was historically used as soil fumigant. Click here to read more about carcinogenic VOCs.

1,2,3-Trichloropropane was found at 102 times above EWG's Health Guideline.

EWG Health Guideline

0.0007 ppb or less

This Utility

0.0715 ppb

National Average

0.00041 ppb

State Average

0.0322 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2019.
ppb = parts per billion

Health Risks

The EWG Health Guideline of 0.0007 ppb for 1,2,3-trichloropropane 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.

VIEW MORE TESTING DATA

Pollution Sources

Industry

Filtering Options

Activated Carbon

Reverse Osmosis

Chromium (hexavalent)

Potential Effect: cancer27x EWG'S HEALTH GUIDELINE
THIS UTILITY0.532 ppb
EWG HEALTH GUIDELINE0.02 ppb
NO LEGAL LIMIT
DETAILS
X

Chromium (hexavalent)

more about
this 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 27 times above EWG's Health Guideline.

EWG Health Guideline

0.02 ppb or less

This Utility

0.532 ppb

National Average

0.484 ppb

State Average

1.66 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2019.
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.

VIEW MORE TESTING DATA

Pollution Sources

Industry

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Haloacetic acids (HAA9)†

Potential Effect: cancer12x EWG'S HEALTH GUIDELINE
THIS UTILITY0.695 ppb
EWG HEALTH GUIDELINE0.06 ppb
NO LEGAL LIMIT
DETAILS
X

Haloacetic acids (HAA9)

more about
this 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 12 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

0.695 ppb

National Average

23.7 ppb

State Average

2.37 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2021.
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.

VIEW MORE TESTING DATA

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Nitrate

Potential Effect: cancer11x EWG'S HEALTH GUIDELINE
THIS UTILITY1.58 ppm
EWG HEALTH GUIDELINE0.14 ppm
LEGAL LIMIT10 ppm
DETAILS
X

Nitrate

more about
this contaminant

Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.

Nitrate was found at 11 times above EWG's Health Guideline.

EWG Health Guideline

0.14 ppm or less

This Utility

1.58 ppm

Legal Limit

10 ppm

National Average

0.935 ppm

State Average

1.02 ppm
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
ppm = parts per million

Health Risks

The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.

VIEW MORE TESTING DATA

Pollution Sources

Agriculture

Runoff & Sprawl

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Nitrate and nitrite

Potential Effect: cancer12x EWG'S HEALTH GUIDELINE
THIS UTILITY1.61 ppm
EWG HEALTH GUIDELINE0.14 ppm
LEGAL LIMIT10 ppm
DETAILS
X

Nitrate and nitrite

more about
this 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 12 times above EWG's Health Guideline.

EWG Health Guideline

0.14 ppm or less

This Utility

1.61 ppm

Legal Limit

10 ppm

National Average

0.888 ppm

State Average

1.04 ppm
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
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.
VIEW MORE TESTING DATA

Pollution Sources

Agriculture

Runoff & Sprawl

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Tetrachloroethylene (perchloroethylene)

Potential Effect: cancer8.9x EWG'S HEALTH GUIDELINE
THIS UTILITY0.536 ppb
EWG HEALTH GUIDELINE0.06 ppb
LEGAL LIMIT5 ppb
DETAILS
X

Tetrachloroethylene (perchloroethylene)

more about
this contaminant

Dry cleaning chemical tetrachloroethylene, or perc, can cause cancer. It pollutes soil and groundwater due to emissions from dry cleaning facilities, and automotive, metalworking and other industries.

Tetrachloroethylene (perchloroethylene) was found at 8.9 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

0.536 ppb

Legal Limit

5 ppb

National Average

0.0211 ppb

State Average

0.00952 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 0.06 ppb for tetrachloroethylene 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.

VIEW MORE TESTING DATA

Pollution Sources

Industry

Runoff & Sprawl

Filtering Options

Activated Carbon

Reverse Osmosis

Total trihalomethanes (TTHMs)†

Potential Effect: cancer3.3x EWG'S HEALTH GUIDELINE
THIS UTILITY0.501 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 3.3 times above EWG's Health Guideline.

EWG Health Guideline

0.15 ppb or less

This Utility

0.501 ppb

Legal Limit

80 ppb

National Average

29.7 ppb

State Average

4.08 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.
VIEW MORE TESTING DATA

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

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; 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.

† 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 , 1,2,4-Trichlorobenzene , 1,2,4-Trimethylbenzene , 1,2-Dichloroethane , 1,2-Dichloropropane , 1,3,5-Trimethylbenzene , 1,3-Butadiene , 1,3-Dichloropropane , 1,3-Dichloropropene , 1,4-Dioxane , 1-butanol , 2,2-Dichloropropane , 2,3,7,8-TCDD (Dioxin) , 2,4,5-T , 2,4,5-TP (Silvex) , 2,4-D , 2,4-DB , 2-methoxyethanol , 2-propen-1-ol , 3-Hydroxycarbofuran , Alachlor (Lasso) , Aldicarb , Aldicarb sulfone , Aldicarb sulfoxide , Aldrin , alpha-Chlordane , Alpha-hexachlorocyclohexane , Antimony , Arsenic , Asbestos , Atrazine , Baygon (Propoxur) , Bentazon (Basagran) , Benzene , Benzo[a]pyrene , Beryllium , Bromobenzene , Bromochloroacetic acid , Bromochloromethane , Bromodichloromethane , Bromomethane , Butachlor , Butylated hydroxyanisole , Cadmium , Carbaryl , Carbofuran , Carbon tetrachloride , Chlorate , Chlordane , Chloroethane , Chloroform , Chloromethane , Chlorpyriphos , cis-1,2-Dichloroethylene , Cobalt , Combined uranium , Cyanide , Dalapon , DCPA mono- and di-acid degradates , Di(2-ethylhexyl) adipate , Di(2-ethylhexyl) phthalate , Dibromoacetic acid , Dibromomethane , Dicamba , Dichloroacetic acid , Dichlorodifluoromethane , Dichloromethane (methylene chloride) , Dichlorprop , Dieldrin , Dimethipin , Dinoseb , Diquat , Endothall , Endrin , Ethoprop , Ethylbenzene , Ethylene dibromide , Germanium , Glyphosate , Haloacetic acids (HAA5) , Heptachlor , Heptachlor epoxide , Hexachlorobenzene (HCB) , Hexachlorocyclopentadiene , Isopropylbenzene , Lindane , m-Dichlorobenzene , Manganese , Mercury (inorganic) , Methiocarb , Methomyl , Methoxychlor , Metolachlor , Metribuzin , Molinate , Molybdenum , Monobromoacetic acid , Monochloroacetic acid , Monochlorobenzene (chlorobenzene) , n-Butylbenzene , n-Propylbenzene , Nitrite , o-Chlorotoluene , o-Dichlorobenzene , o-toluidine , Oxamyl (Vydate) , Oxyflurofen , p-Chlorotoluene , p-Dichlorobenzene , p-Isopropyltoluene , Paraquat , Pentachlorophenol , Perfluorobutane sulfonate (PFBS) , Perfluoroheptanoic acid (PFHPA) , Perfluorohexane sulfonate (PFHXS) , Perfluorononanoic acid (PFNA) , Perfluorooctane sulfonate (PFOS) , Perfluorooctanoic acid (PFOA) , Permethrin , Picloram , Polychlorinated biphenyls (PCBs) , Profenofos , Propachlor , Pyrene , Quinoline , Radium, combined (-226 & -228) , sec-Butylbenzene , Selenium , Simazine , Styrene , Tebuconazole , tert-Butylbenzene , Thallium , Thiobencarb , Toluene , Toxaphene , trans-1,2-Dichloroethylene , Tribufos , Trichloroacetic acid , Trichloroethylene , Trichlorofluoromethane , Vinyl chloride , Xylenes (total)

Wahiawa compliance with legally mandated federal standards:

  • From April 2019 to March 2021, Wahiawa complied with health-based drinking water standards.

Information in this section on Wahiawa 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
1,2,3-Trichloropropane✔✔
Chromium (hexavalent)✔✔
Haloacetic acids (HAA9)✔✔
Nitrate✔✔
Nitrate & nitrite✔✔
Tetrachloroethylene (perchloroethylene)✔✔
Total trihalomethanes (TTHMs)✔✔
OTHER CONTAMINANTS
DETECTED
1,2-Dibromo-3-chloropropane (DBCP)✔✔
Barium✔✔
Bromoform✔✔
Chlorodifluoromethane
Chromium (total)✔✔
Dibromochloromethane✔✔
Fluoride✔
Strontium✔✔
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 MORE

Filter Out Contaminants

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

EWG’S WATER FILTER GUIDE
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