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EWG's Tap Water Database — 2019 UPDATE

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Hillview Water Company-oakhurst/sierra Lakes

EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the California State Water Resources Control Board, 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 2019 - March 2019), tap water provided by this water utility was in compliance with federal health-based drinking water standards.

Utility Details

  • Oakhurst, California
  • Serves: 2,805
  • Data available: 2012—2017
  • Source: Groundwater

Contaminants Detected

9

EXCEED
EWG HEALTH
GUIDELINES

25 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.

Legal ≠ Safe

EWG Health Guidelines fill the gap in outdated government standards.

The federal government’s legal limits are not health-protective. The EPA has not set a new tap water standard in almost 20 years, and some standards are more than 40 years old.

Contaminants Detected

Arsenic

over legal limit
THIS UTILITY12.5 ppb
EWG HEALTH GUIDELINE0.004 ppb
LEGAL LIMIT10 ppb
DETAILS
X

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 3,116 times above EWG's Health Guideline.

EWG Health Guideline

0.004 ppb or less

This Utility

12.5 ppb

Legal Limit

10 ppb

National Average

0.682 ppb

State Average

1.16 ppb
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2015-2017.
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 icon

Agriculture

industry icon

Industry

naturally occuring icon

Naturally Occurring

Filtering Options

reverse osmosis icon

Reverse Osmosis

ion exchange icon

Ion Exchange

Dibromoacetic acid

Potential Effect: 18x EWG'S HEALTH GUIDELINE
THIS UTILITY0.700 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 18 times above EWG's Health Guideline.

EWG Health Guideline

0.04 ppb or less

This Utility

0.7 ppb

National Average

1.17 ppb

State Average

2.21 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2015-2017.
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

Molybdenum

Potential Effect: change in blood chemistry2.1x EWG'S HEALTH GUIDELINE
THIS UTILITY83.1 ppb
EWG HEALTH GUIDELINE40 ppb
NO LEGAL LIMIT
DETAILS
X

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.

Molybdenum was found at 2.1 times above EWG's Health Guideline.

EWG Health Guideline

40 ppb or less

This Utility

83.1 ppb

National Average

1.52 ppb

State Average

3.44 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2012-2017.
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 icon

Industry

naturally occuring icon

Naturally Occurring

Filtering Options

reverse osmosis icon

Reverse Osmosis

ion exchange icon

Ion Exchange

Nitrate

Potential Effect: cancer2.7x EWG'S HEALTH GUIDELINE
THIS UTILITY0.385 ppm
EWG HEALTH GUIDELINE0.14 ppm
LEGAL LIMIT10 ppm
DETAILS
X

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 2.7 times above EWG's Health Guideline.

EWG Health Guideline

0.14 ppm or less

This Utility

0.385 ppm

Legal Limit

10 ppm

National Average

0.937 ppm

State Average

1.84 ppm
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2015-2017.
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.

Pollution Sources

agriculture icon

Agriculture

urban area icon

Runoff & Sprawl

naturally occuring icon

Naturally Occurring

Filtering Options

reverse osmosis icon

Reverse Osmosis

ion exchange icon

Ion Exchange

Nitrate and nitrite

Potential Effect: cancer3.8x EWG'S HEALTH GUIDELINE
THIS UTILITY0.527 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 3.8 times above EWG's Health Guideline.

EWG Health Guideline

0.14 ppm or less

This Utility

0.527 ppm

Legal Limit

10 ppm

National Average

0.891 ppm

State Average

1.73 ppm
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2015-2017.
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 icon

Agriculture

urban area icon

Runoff & Sprawl

naturally occuring icon

Naturally Occurring

Filtering Options

reverse osmosis icon

Reverse Osmosis

ion exchange icon

Ion Exchange

Radium, combined (-226 & -228)

Potential Effect: cancer20x EWG'S HEALTH GUIDELINE
THIS UTILITY1.01 pCi/L
EWG HEALTH GUIDELINE0.05 pCi/L
LEGAL LIMIT5 pCi/L
DETAILS
X

Radium, combined (-226 & -228)

more about
this 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.

Radium, combined (-226 & -228) was found at 20 times above EWG's Health Guideline.

EWG Health Guideline

0.05 pCi/L or less

This Utility

1.01 pCi/L

Legal Limit

5 pCi/L

National Average

0.47 pCi/L

State Average

0.2 pCi/L
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2012-2017.
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 icon

Industry

naturally occuring icon

Naturally Occurring

Filtering Options

reverse osmosis icon

Reverse Osmosis

ion exchange icon

Ion Exchange

Tetrachloroethylene (perchloroethylene)

Potential Effect: cancer23x EWG'S HEALTH GUIDELINE
THIS UTILITY1.38 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 23 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

1.38 ppb

Legal Limit

5 ppb

National Average

0.0229 ppb

State Average

0.0722 ppb
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2015-2017.
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.

Pollution Sources

industry icon

Industry

urban area icon

Runoff & Sprawl

Filtering Options

carbon filter icon

Activated Carbon

reverse osmosis icon

Reverse Osmosis

Total trihalomethanes (TTHMs)

Potential Effect: cancer8.3x EWG'S HEALTH GUIDELINE
THIS UTILITY1.24 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 8.3 times above EWG's Health Guideline.

EWG Health Guideline

0.15 ppb or less

This Utility

1.24 ppb

Legal Limit

80 ppb

National Average

30.1 ppb

State Average

31.1 ppb
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2015-2017.
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

Uranium

over legal limit
THIS UTILITY51.32 pCi/L
EWG HEALTH GUIDELINE0.43 pCi/L
LEGAL LIMIT20 pCi/L
DETAILS
X

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 119 times above EWG's Health Guideline.

EWG Health Guideline

0.43 pCi/L or less

This Utility

51.32 pCi/L

Legal Limit

20 pCi/L

National Average

1.09 pCi/L

State Average

2.65 pCi/L
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2012-2017.
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 icon

Industry

naturally occuring icon

Naturally Occurring

Filtering Options

reverse osmosis icon

Reverse Osmosis

ion exchange icon

Ion Exchange

Includes chemicals detected in 2015-2017 for which annual utility averages exceeded the federal Maximum Contaminant Level (MCL); chemicals detected in 2015-2017 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; radiological contaminants detected between 2012 and 2017.


Other Contaminants Tested


Contaminants detected between 2012 and 2014 and were not part of EPA's UCMR-3 testing program or radiologicals:

Chromium (total)

 

Chemicals tested for but not detected from 2012 to 2017:

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-Dibromo-3-chloropropane (DBCP), 1,2-Dichloroethane, 1,2-Dichloropropane, 1,3,5-Trimethylbenzene, 1,3-Butadiene, 1,3-Dichloropropane, 1,3-Dichloropropene, 1,4-Dioxane, 2,2-Dichloropropane, Alachlor (Lasso), Antimony, Asbestos, Atrazine, Barium, Benzene, Beryllium, Bromobenzene, Bromochloromethane, Bromomethane, Cadmium, Carbon tetrachloride, Chlorodifluoromethane, Chloroethane, cis-1,2-Dichloroethylene, cis-1,3-Dichloropropene, Cobalt, Dibromomethane, Dichloroacetic acid, Dichlorodifluoromethane, Dichloromethane (methylene chloride), Ethyl tert-butyl ether, Ethylbenzene, Ethylene dibromide, Germanium, Haloacetic acids (HAA5), Hexachlorobutadiene, Isopropyl ether, Isopropylbenzene, m-Dichlorobenzene, Mercury (inorganic), Methyl ethyl ketone, Methyl isobutyl ketone, Monobromoacetic acid, Monochloroacetic acid, Monochlorobenzene (chlorobenzene), MTBE, n-Butylbenzene, n-Propylbenzene, Naphthalene, Nitrite, o-Chlorotoluene, o-Dichlorobenzene, p-Chlorotoluene, p-Dichlorobenzene, p-Isopropyltoluene, Perchlorate, Perfluorobutane sulfonate (PFBS), Perfluoroheptanoic acid (PFHPA), Perfluorohexane sulfonate (PFHXS), Perfluorononanoic acid (PFNA), Perfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA), sec-Butylbenzene, Silver, Simazine, Styrene, Tellurium, tert-Amyl methyl ether, tert-Butylbenzene, Thallium, trans-1,2-Dichloroethylene, trans-1,3-Dichloropropene, Trichloroacetic acid, Trichloroethylene, Trichlorofluoromethane, Trichlorotrifluoroethane, Vinyl chloride, Xylenes (total)

Hillview Water Company-oakhurst/sierra Lakes compliance with legally mandated federal standards:

  • From April 2016 to March 2019, Hillview Water Company-oakhurst/sierra Lakes complied with health-based drinking water standards.
  • 12 QUARTERS
    in violation of any federal drinking water standard from April 2016 to March 2019

Information in this section on Hillview Water Company-oakhurst/sierra Lakes 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
Arsenic
Dibromoacetic acid
Molybdenum
Nitrate
Nitrate & nitrite
Radium, combined (-226 & -228)
Tetrachloroethylene (perchloroethylene)
Total trihalomethanes (TTHMs)
Uranium, combined (pCi/L)
OTHER CONTAMINANTS
DETECTED
Acetone
Aluminum
Bromodichloromethane
Bromoform
Chlorate
Chloroform
Chloromethane
Chromium (hexavalent)
Dibromochloromethane
Fluoride
Manganese
Selenium
Strontium
tert-Butyl alcohol
Toluene
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