EWG's Tap Water Database — 2021 UPDATE



Status: National drinking water standard exists


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. Read More.

Multiple forms of uranium can be detected in water, including uranium-234, uranium-235 and uranium-238. Uranium-234 is the most toxic form of uranium for human health.




states detected


utilities detected

80 million

people served


states over health guideline


utilities over health guideline

61 million

people served over health guideline

Health concerns for uranium


Harm to the kidney

State and national drinking water standards and health guidelines

EWG Health Guideline 0.43 pCi/L

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.

EPA Maximum Contaminant
Level (MCL) 20 pCi/L

pCi/L = picocuries per liter

States reporting uranium in drinking water

State UtilitiesPeople Served UtilitiesPeople Served
New York252980,4294863,857,691
New Jersey972,075,1461083,048,387
New Mexico4641,801,5064711,872,233
North Carolina357164,953409332,707
North Dakota146146,145194311,365
New Hampshire276104,396349248,835
West Virginia26,650330,945
South Carolina3220,6983120,655
South Dakota2214,3522314,502
Rhode Island91,35691,356

Filtering technologies that reduce uranium

reverse osmosis icon

Reverse Osmosis

ion exchange icon

Ion Exchange

Utilities with the highest amounts of uranium, 2014-2019

UtilityLocationTestsAverage levelPeople served
Two Twenty Four Mobile Home PkNorth Fork, CA1 of 189.00 pCi/L30
Queen's Inn By The RiverOakhurst, CA5 of 581.00 pCi/L50
Crawford*Crawford, GA5 of 569.27 pCi/L1,170
AltoAlto, GA10 of 1061.12 pCi/L2,545
Md#06 Lake Shore ParkMadera, CA10 of 1057.69 pCi/L130
Glen Acres Water Co-opLordsburg, NM19 of 1954.31 pCi/L180
South Kingstown Nursing and RehabWest Kingston, RI6 of 653.48 pCi/L175
Riviera WCIDRiviera, TX28 of 2849.54 pCi/L729
Sierra Linda Mutual Water CompanyNorth Fork, CA12 of 1247.74 pCi/L180
Oconee Springs Landing S/dAtlanta, GA2 of 245.40 pCi/L346
Hillview Water Company-oakhurst/sierra Lakes*Oakhurst, CA223 of 22742.72 pCi/L2,805
Broadview Terrace Mutual Water CompanyOakhurst, CA223 of 22742.72 pCi/L510
Pecan Grove Mobile Home ParkSan Antonio, TX8 of 842.17 pCi/L81
Mitchells Camp Family AssociationPalo Verde, CA10 of 1042.01 pCi/L175
East Three Rivers MutualThree Rivers, CA3 of 341.69 pCi/L28
Sheridan Lake Water CompanySheridan Lake, CO12 of 1240.03 pCi/L160
Csa 70-f MorongoVictorville, CA62 of 6239.47 pCi/L450
Buttonwillow County Water DistrictButtonwillow, CA4 of 439.20 pCi/L1,266
Md#42 Still MeadowMadera, CA9 of 938.21 pCi/L100
Guatay Mutual Benefit CorporationGuatay, CA42 of 4437.98 pCi/L100
Rosamond Mobilehome ParkTustin, CA24 of 2435.63 pCi/L175
Meadow Lakes SubdivisionCrawford, GA1 of 135.00 pCi/L81
Rainbird Valley Mutual Water CompanyWeldon, CA42 of 4334.86 pCi/L188
Daggett Community Services DistrictDaggett, CA12 of 1234.36 pCi/L795
White PlainsWhite Plains, GA7 of 1034.04 pCi/L437
Knoll EnterprisesLudlow, CA38 of 4032.02 pCi/L500
Eagles Nest EstatesChadron, NE3 of 331.23 pCi/L52
Kelvin Simmons Co-opSan Tan Valley, AZ6 of 631.09 pCi/L25
Strawberry Fields Mobile Home ParkPlant City, FL26 of 2630.69 pCi/L250
Rancho Santa Teresa Mw CompanyRamona, CA39 of 3929.84 pCi/L74
Martin's Mobile Home CourtNewman, CA13 of 1329.71 pCi/L60
Beverly, City ofBeverly, KS6 of 629.52 pCi/L148
Rio Brazos Water SystemChoctaw, TX24 of 2428.97 pCi/L108
Jim Wells County Fresh Water Supply District 1Ben Bolt, TX24 of 2428.71 pCi/L1,890
Santa Cruz Water AssociationSanta Cruz, NM47 of 4728.64 pCi/L343
Piedmont Municpal AuthorityPiedmont, OK6 of 628.21 pCi/L7,542
Johnson Creek Water Users AssociationTonasket, WA15 of 1528.10 pCi/L48
R.s. Mutual Water CompanyWofford Heights, CA23 of 2327.57 pCi/L67
Cliffs At Keowee (sc3950009)Seneca, SC4 of 427.24 pCi/L23
Byram Hmwnrs Association WaterPhillipsburg, NJ10 of 1127.04 pCi/L400
Ojo Caliente Mutual Domestic Water Consumers AssociationOjo Caliente, NM49 of 4926.65 pCi/L226
Martinsburg, Village ofAllen, NE31 of 3126.56 pCi/L94
Haystack EstatesWestford, MA27 of 3326.36 pCi/L60
Barrett Lake Mobile Home and Rv LLCDulzura, CA20 of 2126.30 pCi/L150
Old River Mutual Water CompanyBakersfield, CA23 of 2326.09 pCi/L60
Trotter`s Ridge SubdivisionWatkinsville, GA3 of 325.80 pCi/L187
Pecan Tree Water AssociationNoble, OK30 of 3025.76 pCi/L22
Valley Estates Water & Sewer AssociationFairview, NM25 of 2525.70 pCi/L194
Trampas Mutual Domestic Water Consumers AssociationChamisal, NM25 of 2525.57 pCi/L132
Round Mountain Water CompanyBakersfield, CA48 of 4825.13 pCi/L50

* This water utility supplies finished drinking water to at least one other water utility. The purchasing utility is not required to test for or report Uranium, but it likely has the contaminant in its water supply.

UtilityLocationTestsAverage levelPeople served
Warrington Twp Water&sew DeptWarrington, PA24 of 2420.00 pCi/L21,588
City of SangerSanger, CA1 of 119.00 pCi/L25,664
City of Scottsbluff*Scottsbluff, NE36 of 3617.11 pCi/L15,030
City of North Platte*North Platte, NE6 of 614.93 pCi/L25,000
City of Grand Island*Grand Island, NE41 of 4114.31 pCi/L51,440
Dona Ana MDWCADona Ana, NM12 of 1214.01 pCi/L16,217
City of Hastings*Hastings, NE15 of 1513.93 pCi/L25,224
City of LexingtonLexington, NE20 of 2013.84 pCi/L10,230
Centerville City Water SystemCenterville, UT2 of 213.63 pCi/L16,000
White City WIDSandy, UT2 of 213.58 pCi/L15,800
City of Garden City*Garden City, KS2 of 213.11 pCi/L26,546
Mission Springs WDDesert Hot Springs, CA182 of 18312.43 pCi/L34,626
West Kern Water DistrictTaft, CA31 of 3111.68 pCi/L21,181
City of HerefordHereford, TX21 of 2111.53 pCi/L15,370
Twentynine Palms Water DistrictTwentynine Palms, CA58 of 5811.42 pCi/L18,600
Murray City Water System*Murray, UT3 of 311.26 pCi/L36,000
Carson City Public Works*Carson City, NV819 of 82111.18 pCi/L56,000
South Adams County Water and Sanitation DistrictCommerce City, CO17 of 1710.95 pCi/L63,808
Midvale City Water SystemMidvale, UT5 of 510.72 pCi/L33,000
Espanola Water System*Espanola, NM10 of 1010.65 pCi/L12,012
East Pasadena Water CompanyPasadena, CA6 of 610.62 pCi/L10,978
Desert Water AgencyPalm Springs, CA44 of 4410.20 pCi/L83,710
City of KermanKerman, CA16 of 179.99 pCi/L14,068
Farmington City Water SystemFarmington, UT2 of 29.92 pCi/L24,000
City of MidlandMidland, TX2 of 29.88 pCi/L132,950
Pasadena*Pasadena, CA23 of 249.71 pCi/L165,740
City of Dodge CityDodge City, KS1 of 19.60 pCi/L27,329
Waterpro IncDraper, UT2 of 29.51 pCi/L28,000
Burbank Water DepartmentBurbank, CA2 of 29.05 pCi/L105,543
City of Corona*Corona, CA39 of 568.99 pCi/L155,896
City of CeresCeres, CA235 of 2358.92 pCi/L42,666
City of ElkoElko, NV44 of 458.90 pCi/L20,451
Northwest Park MUDHouston, TX6 of 68.86 pCi/L17,406
Global Water - Santa Cruz Water CompanyMaricopa, AZ94 of 968.61 pCi/L17,005
City of KunaKuna, ID20 of 218.39 pCi/L22,830
MustangMustang, OK2 of 28.07 pCi/L15,435
California Water Service (CWS) - SalinasSan Jose, CA171 of 1787.93 pCi/L106,858
Golden State Water Company - Bay PointRancho Cordova, CA1 of 17.80 pCi/L22,258
City of LemooreLemoore, CA1 of 17.80 pCi/L24,945
City of Garden GroveGarden Grove, CA37 of 377.75 pCi/L170,883
Golden State Water Company - West OrangeAnaheim, CA20 of 217.75 pCi/L114,016
California Water Service (CWS) - SelmaSan Jose, CA6 of 77.71 pCi/L24,587
City of Riverside*Riverside, CA308 of 3087.69 pCi/L303,871
South Orange Water DepartmentSouth Orange, NJ1 of 17.66 pCi/L16,964
City of Fresno*Fresno, CA38 of 407.65 pCi/L522,352
City of RiponRipon, CA4 of 67.45 pCi/L14,915
City of CorcoranCorcoran, CA2 of 27.41 pCi/L24,813
City of EnglewoodEnglewood, CO1 of 17.37 pCi/L46,541
City of KearneyKearney, NE24 of 247.35 pCi/L30,919
Military Highway WSC - ProgresoProgreso, TX4 of 47.30 pCi/L11,136

* This water utility supplies finished drinking water to at least one other water utility. The purchasing utility is not required to test for or report Uranium, but it likely has the contaminant in its water supply.