Mi-wuk Heights Mutual Water Company

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 2021 - March 2021), tap water provided by this water utility was in compliance with federal health-based drinking water standards.

Utility Details

Tuolumne County, California
Serves: 352
Data available: 2014-2019
Source: Groundwater

Contaminants Detected

EXCEED
EWG HEALTH
GUIDELINES

4 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

Filter contaminants out Contact Your Local Official What About Lead?

Looking for a countertop water filter?

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Contaminants Detected

VIEW: EXCEED GUIDELINES OTHER DETECTED

Nitrate

Potential Effect: cancer3.3x EWG'S HEALTH GUIDELINE

THIS UTILITY0.467 ppm

EWG HEALTH GUIDELINE0.14 ppm

LEGAL LIMIT10 ppm

DETAILS

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.

Chromium (total)

THIS UTILITY7.00 ppb

NO EWG HEALTH GUIDELINE

LEGAL LIMIT100 ppb

DETAILS

Dichloromethane (methylene chloride)

THIS UTILITY3.60 ppb

EWG HEALTH GUIDELINE4 ppb

LEGAL LIMIT5 ppb

DETAILS

Fluoride

THIS UTILITY0.0400 ppm

NO EWG HEALTH GUIDELINE

LEGAL LIMIT4 ppm

DETAILS

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 authori.

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 , 1,2,3-trimethylbenzene (hemellitol) , 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-Dichloropropane , 1,3-Dichloropropene , 2,2-Dichloropropane , 2-Chloroethylvinyl ether , Alachlor (Lasso) , Aluminum , Antimony , Arsenic , Atrazine , Barium , Benzene , Beryllium , Bromacil , Bromobenzene , Bromochloromethane , Bromodichloromethane , Bromoform , Bromomethane , Butachlor , Cadmium , Carbon tetrachloride , Chloroethane , Chloroform , Chloromethane , Chromium (hexavalent) , cis-1,2-Dichloroethylene , Diazinon (Spectracide) , Dibromochloromethane , Dibromomethane , Dichlorodifluoromethane , Dimethoate , Ethyl tert-butyl ether , Ethylbenzene , Ethylene dibromide , Hexachlorobutadiene , Isopropyl ether , Isopropylbenzene , m-Dichlorobenzene , Manganese , Mercury (inorganic) , Methyl ethyl ketone , Methyl isobutyl ketone , Metolachlor , Metribuzin , Molinate , Monochlorobenzene (chlorobenzene) , MTBE , n-Butylbenzene , n-Propylbenzene , Naphthalene , Nitrate & nitrite , Nitrite , o-Chlorotoluene , o-Dichlorobenzene , p-Chlorotoluene , p-Dichlorobenzene , p-Isopropyltoluene , Perchlorate , Prometryn , Radium, combined (-226 & -228) , sec-Butylbenzene , Selenium , Silver , Simazine , Styrene , Terbufos , tert-Amyl methyl ether , tert-Butyl alcohol , tert-Butylbenzene , Tetrachloroethylene (perchloroethylene) , Thallium , Thiobencarb , Toluene , trans-1,2-Dichloroethylene , Tribromoacetic acid , Trichloroethylene , Trichlorofluoromethane , Trichlorotrifluoroethane , Vinyl chloride , Xylenes (total)