Environmental Issues > Water Main Page > All Water Documents

Arsenic and Old Laws
A Scientific and Public Health Analysis of Arsenic Occurrence in Drinking Water, Its Health Effects, and EPA's Outdated Arsenic Tap Water Standard

Top of Report


Table 4

Highest Average Arsenic Levels in Water Systems Serving over 10,000 People (Ranked by Largest Population First)

Natural Resources Defense Council, February 2000.
Based on EPA's 25-State Arsenic Database of Samples Taken and Reported to States from 19801998 (see important note below).
Contact Your Water System or State for All Sample Results.
Rank Water System Name State County Population Served Low Est. of Average Arsenic Level(ppb) Best Est. of Average Arsenic Level (ppb) # Samples in Which Arsenic Was Detected # of Samples in Which Arsenic Was Not Detected Min Level Found (ppb) Max Level Found Most Recent Sample in EPA Database (ppb) Date of Most Recent Sample in EPA Database
1 OKLAHOMA UNIVERSITY OK OK 22738 78 78 20 0 8.0 193.0 (av) 180.3 2/13/96
2 HANFORD, CITY OF CA KINGS 37000 51 51 51 1 <10.0 136.0 37.0 11/14/94
3 NORMAN OK OK 80000 36 36 25 2 2.0 120.0 46.0 12/1/98
4 ANDREWS CITY OF TX ANDREWS 11061 35 35 2 0 33.3 36.2 33.3 8/15/96
5 YUKON OK OK 20000 35 35 2 0 32.0 37.0 37.0 7/20/95
6 CITY OF CHINO HILLS CA SAN BERNARDIN 49000 28 30 30 19 2.0 105.0 (av) 54.6 8/27/96
7 ARVIN COMMUNITY SERVICES DIST CA KERN 10700 30 30 98 0 7.8 60.0 30.0 12/21/95
8 WEATHERFORD OK OK 10400 29 29 5 0 20.0 40.0 31.0 6/4/96
9 CALIFORNIA MENS COLONY CA SAN LUIS OBIS 15000 23 26 1 16 <1.0 390.0 <2.0 12/19/94
10 US ARMY FORT IRWIN CA SAN BERNARDIN 17000 24 25 24 8 <5.0 70.0 13.1 8/18/95
11 CORCORAN, CITY OF CA KINGS 17560 23 23 19 3 <6.0 44.0 (av) 24.8 5/31/95
12 DELANO, CITY OF CA KERN 31235 22 23 32 4 <2.0 70.0 36.0 2/2/96
13 INDIAN WELLS VALLEY W.D. CA KERN 32630 21 23 98 58 <2.0 460.0 (av) 13.4 1/13/97
14 NELLIS AIR FORCE BASE AREA I NV CLARK 18100 21 21 2 0 21.0 21.0 (av) 21.0 2/14/96
15 LEMOORE, CITY OF CA KINGS 15806 21 21 16 0 7.0 36.0 (av) 13.8 6/13/96
16 M.D.O.T-GRAYLING REST 1&2,R403 MI CRAWFORD 12000 20 20 1 0 20.2 20.2 20.2 6/5/95
17 AZ WATER CO-APACHE JCT S AZ PINAL 34900 16 17 15 2 <10.0 32.0 (av) 15.0 3/10/98
18 AZ WATER CO-CASA GRANDE AZ PINAL 36500 16 17 50 12 <5.0 62.0 (av) 23.0 8/20/96
19 SUN CITY WEST AZ MARICOPA 40000 14 16 19 9 <10.0 34.0 (av) 19.5 7/15/97
20 NEW MEXICO UTILITIES, INC. NM BERNALILLO 14000 15 15 8 0 7.0 30.0 11.0 6/24/98
21 CITY OF LAKEWOOD CA LOS ANGELES 66000 14 15 39 19 <2.0 100.0 (av) 4.1 8/6/96
22 AVONDALE, CITY PUBLIC WO AZ MARICOPA 22000 13 15 17 14 3.7 50.0 (best av) 10.8 2/24/98
23 LOS ANGELES CO WW DIST 4 & 34-LANCASTER CA LOS ANGELES 96073 12 15 82 85 <2.0 103.0 (av) 10.7 12/26/96
24 ALBUQUERQUE WATER SYSTEM NM BERNALILLO 417279 14 14 188 15 <1.0 60.0 (av) 9.5 1/6/98
25 HILLCREST WATER COMPANY 1,2,3,4 CA SUTTER 10062 13 13 23 5 <5.0 36.0 36.0 5/12/97
26 SCWC - ARTESIA CA LOS ANGELES 35731 11 13 15 18 <2.0 51.0 <2.0 5/23/96
27 LAKE HAVASU CITY AZ MOHAVE 37000 10 13 30 49 <5.0 81.0 (best av) 12.8 3/20/97
28 MOORE OK OK 40300 12 13 59 19 <2.0 42.0 (av) 34.5 11/30/98
29 ELK GROVE WATER WORKS CA SACRAMENTO 23000 12 13 18 2 <5.0 30.0 (av) 13.0 10/5/95
30 MOUNDS VIEW MN RAMSEY 12700 12 13 6 1 1.0 34.0 29.0 11/12/97
31 CITY OF RIO RANCHO SEWER AND WASTEWATER SERV NM SANDOVAL 49999 12 12 39 8 <0.6 53.0 20.0 7/31/97
32 PARADISE V WATER CO-AM W AZ MARICOPA 12000 12 12 51 3 0.7 40.0 (av) 9.7 5/13/96
33 CITY OF ELKO NV ELKO 10000 12 12 1 0 12.0 12.0 12.0 8/1/94
34 EAST NILES CSD CA KERN 21500 11 12 27 8 2.3 50.0 7.1 12/18/95
35 VICTORIA CITY OF TX VICTORIA 67353 11 12 3 2 <2.0 23.1 (best av) 11.2 8/13/96
36 SCWMD LAGUNA/VINEYARD CA SACRAMENTO 20259 11 12 28 4 <4.0 36.0 (av) 14.5 5/13/96
37 HCO MUD NO 53 TX HARRIS 19227 12 12 2 0 6.8 16.2 6.8 5/28/96
38 WOODBURN, CITY OF OR MARION 15225 11 11 6 0 6.0 18.0 (av) 11.3 4/21/92
39 SCOTTSDALE, MUNIC WATER AZ MARICOPA 174170 10 11 149 55 <1.0 50.0 (av) 8.0 2/25/98
40 MIDLAND CITY OF TX MIDLAND 97458 11 11 7 2 <2.0 31.9 (av) 4.6 6/11/96
41 TRUCKEE-DONNER PUD, MAIN CA NEVADA 14200 9 11 7 13 <4.0 41.0 (best av) 13.6 1/26/93
42 BELLFLOWER - SOMERSET MWC CA LOS ANGELES 24000 8 11 4 17 <2.0 160.0 (best av) 1.5 11/15/95
43 GALT, CITY OF CA SACRAMENTO 12000 9 11 21 13 2.7 36.0 (av) 8.9 4/3/96
44 JEFFERSON CO CONS PWSD C1 MO MOJEFFERSON 30000 10 10 1 0 10.1 10.1 10.1 9/11/96
45 BEALE AIR FORCE BASE CA YUBA 10000 5 10 4 22 <10.0 50.0 (av) <10.0 8/23/93
46 MANTECA, CITY OF CA SAN JOAQUIN 44500 7 10 23 25 8.1 25.9 (av) 12.2 4/9/97
47 MESA, MUNIC WATER DEPT. AZ MARICOPA 350000 7 10 94 127 0.5 50.0 (best av) 8.4 5/21/97
* Important note regarding arsenic levels in individual water systems listed in this report: The information on arsenic levels in public water systems included in the NRDC report Arsenic and Old Laws is derived from the U.S. Environmental Protection Agency's (EPA) 25-state arsenic database, which includes samples taken from 1980 to 1998. NRDC has not independently verified these data, which EPA collected from state drinking water program officials, and compiled into the 25-state arsenic database. Additional sampling may have been completed for some water systems after the EPA database was compiled. To verify information on all sampling completed to date for a public water system, contact your state drinking water program (call EPA's drinking water Hotline at 800 426-4791 for state contacts) or your water system.

Corrections: Because of an error in data reporting by the state of California, in the print version of this report and the earlier online version, Alameda County Water District, City of Antioch Water Department, and City of Santa Clara Water and Sewer Utilities were incorrectly included in charts identifying water systems with high average arsenic levels.

NRDC has been informed that the monitoring results reported to the state of California by the City of Milpitas, which the state then reported to US EPA (and ultimately were reported by NRDC based on EPA's database), were for emergency wells not currently in use. This information was not indicated in EPA's database. The City of Milpitas has provided information indicating that the water used by the City of Milpitas has been consistently below 2 parts per billion (ppb).


Sign up for NRDC's online newsletter

See the latest issue >

Water on Switchboard

NRDC experts write about water efficiency, green infrastructure and climate on the NRDC blog.


Recent Water Posts

State's Refusal to Use Sound Science Continues to Delay the Bay Delta Conservation Plan
posted by Doug Obegi, 4/29/13
Floods, Droughts and Agriculture
posted by Ben Chou, 4/29/13
Home Run! Appeals Court Upholds EPA Action to Stop Giant, Polluting Mountaintop Removal Mine
posted by Jon Devine, 4/25/13
Give the Gift That Will Make a Difference: A Long Cool Drink

NRDC Gets Top Ratings from the Charity Watchdogs

Charity Navigator awards NRDC its 4-star top rating.
Worth magazine named NRDC one of America's 100 best charities.
NRDC meets the highest standards of the Wise Giving Alliance of the Better Business Bureau.


Donate now >

Related Links

Share | |