The Power of Information

National Drinking Water Database


Pomona - City, Water Dept. Utilities - Los Angeles, CA


Serves 156,500 people

Chromium (hexavalent)

Chromium is a metal that pollutes drinking water due to discharge from steel and pulp mills and erosion of natural deposits.
 
This Drinking Water System
Test Days Exceeding Health GuidelinesDefinition of what this is
2 days
Test Days Exceeding Legal LimitsNumber of days in which the samples taken in that day exceed the Maximum Contaminant Level (Depending on the contaminant and its MCL, that may or may not trigger an MCL violation. Some MCLs are based on averages spanning several months to a year)
2 days
Test DaysNumber of days in which this chemical has reported results in the data we received from the State
136 days
Tests ConductedNumber of individual tests done for this contaminant
286 tests

Testing Summary

ContaminantAverage/
Maximum
Result
Health Limit
Exceeded
Legal Limit
Exceeded

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
Chromium (hexavalent)Chromium is a metal that pollutes drinking water due to discharge from steel and pulp mills and erosion of natural deposits.12.44 ppb
170 ppb
YesYes
100 ppb
NOTE: Each dot in the above graph represents one month.
* Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Health Based and Legal Limits for Chromium (hexavalent)

Health Based Limits for Chromium (hexavalent)

StandardDescriptionLevel
Maximum Contaminant Limit (MCL)The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency.100 ppb

Testing Results

Testing DateAverage
Result
Samples taken that dayNumber of Non-DetectsRange of Results
2009-04-024.5 ppb104.5 ppb
2009-03-023.5 ppb103.5 ppb
2009-02-110 ppb110 ppb
2009-02-022.8 ppb102.8 ppb
2009-01-140.98 ppb100.98 ppb
2009-01-064.43 ppb301 to 7.3 ppb
2009-01-052.9 ppb102.9 ppb
2008-12-2312 ppb1012 ppb
2008-12-012.4 ppb102.4 ppb
2008-11-102.8 ppb102.8 ppb
2008-10-286.8 ppb106.8 ppb
2008-10-169.7 ppb205.4 to 14 ppb
2008-10-151.87 ppb301.3 to 2.6 ppb
2008-10-084.45 ppb610 to 8 ppb
2008-10-063.2 ppb103.2 ppb
2008-09-022.6 ppb102.6 ppb
2008-08-042.3 ppb102.3 ppb
2008-07-226.6 ppb106.6 ppb
2008-07-021.95 ppb200.9 to 3 ppb
2008-07-011.1 ppb101.1 ppb
2008-06-0411 ppb1011 ppb
2008-06-022.7 ppb102.7 ppb
2008-05-2822.23 ppb306.7 to 47 ppb
2008-05-14130 ppb10130 ppb
2008-05-053 ppb103 ppb
2008-05-0118.77 ppb303.5 to 49 ppb
2008-04-161.55 ppb201.2 to 1.9 ppb
2008-04-080.21 ppb210 to 0.42 ppb
2008-04-0715 ppb2014 to 16 ppb
2008-04-027 ppb1200.51 to 22 ppb
2008-04-013.35 ppb202.5 to 4.2 ppb
2008-03-2612 ppb1012 ppb
2008-03-033 ppb103 ppb
2008-02-043.6 ppb103.6 ppb
2008-01-316.5 ppb106.5 ppb
2008-01-241.2 ppb101.2 ppb
2008-01-073.4 ppb103.4 ppb
2008-01-021.1 ppb101.1 ppb
2007-12-033.9 ppb103.9 ppb
2007-11-201.55 ppb201.2 to 1.9 ppb
2007-11-066.2 ppb204.6 to 7.8 ppb
2007-10-170.45 ppb200.4 to 0.5 ppb
2007-10-100.58 ppb200.54 to 0.61 ppb
2007-10-099.85 ppb1201.8 to 27 ppb
2007-10-035.7 ppb105.7 ppb
2007-10-027.27 ppb400.98 to 19 ppb
2007-09-055.4 ppb105.4 ppb
2007-08-145.8 ppb105.8 ppb
2007-07-170.86 ppb100.86 ppb
2007-07-035.3 ppb105.3 ppb
2007-06-13170 ppb10170 ppb
2007-06-066.7 ppb106.7 ppb
2007-05-0255.43 ppb302.3 to 150 ppb
2007-05-017.6 ppb107.6 ppb
2007-04-177.5 ppb107.5 ppb
2007-04-125.2 ppb105.2 ppb
2007-04-1114.5 ppb2010 to 19 ppb
2007-04-063.66 ppb200.41 to 6.9 ppb
2007-04-0517.4 ppb207.8 to 27 ppb
2007-04-047.77 ppb1500.49 to 28 ppb
2007-04-034 ppb300.3 to 7.6 ppb
2007-03-066.4 ppb106.4 ppb
2007-02-067.5 ppb107.5 ppb
2007-01-2396 ppb1096 ppb
2007-01-036.3 ppb106.3 ppb
2006-12-120.76 ppb100.76 ppb
2006-12-057.3 ppb107.3 ppb
2006-11-076.7 ppb106.7 ppb
2006-10-311.6 ppb101.6 ppb
2006-10-260.52 ppb400.48 to 0.61 ppb
2006-10-259.03 ppb304.4 to 17 ppb
2006-10-1817.57 ppb307.7 to 35 ppb
2006-10-1228.5 ppb2022 to 35 ppb
2006-10-1116.4 ppb207.8 to 25 ppb
2006-10-1014.1 ppb202.2 to 26 ppb
2006-10-046.13 ppb600.35 to 12 ppb
2006-10-036.92 ppb504.3 to 10 ppb
2006-09-066 ppb106 ppb
2006-08-026.4 ppb106.4 ppb
2006-07-057.6 ppb107.6 ppb
2006-06-077.6 ppb107.6 ppb
2006-05-109.6 ppb109.6 ppb
2006-05-0316 ppb1016 ppb
2006-05-026.2 ppb106.2 ppb
2006-04-240.33 ppb100.33 ppb
2006-04-1917.39 ppb903.8 to 44 ppb
2006-04-115.5 ppb105.5 ppb
2006-04-079.6 ppb203.2 to 16 ppb
2006-04-0510.43 ppb307.3 to 12 ppb
2006-04-045.9 ppb105.9 ppb
2006-03-015.3 ppb105.3 ppb
2006-02-0115.55 ppb206.1 to 25 ppb
2006-01-045.7 ppb105.7 ppb
2005-12-1331 ppb1031 ppb
2005-12-065.4 ppb105.4 ppb
2005-11-025.2 ppb105.2 ppb
2005-10-278.5 ppb207 to 10 ppb
2005-10-2622.35 ppb205.7 to 39 ppb
2005-10-2011.85 ppb208.7 to 15 ppb
2005-10-1111.03 ppb303.2 to 22 ppb
2005-10-058.08 ppb507.3 to 10 ppb
2005-10-044.5 ppb104.5 ppb
2005-09-2742 ppb1042 ppb
2005-09-064.8 ppb104.8 ppb
2005-08-034.63 ppb310 to 8.5 ppb
2005-07-0522.85 ppb204.7 to 41 ppb
2005-06-075.6 ppb105.6 ppb
2005-06-0244 ppb1044 ppb
2005-05-240.82 ppb100.82 ppb
2005-05-0518.07 ppb304.9 to 44 ppb
2005-05-043.09 ppb200.38 to 5.8 ppb
2005-04-260.5 ppb100.5 ppb
2005-04-251.8 ppb201.7 to 1.9 ppb
2005-04-147.67 ppb1104.4 to 15 ppb
2005-04-1217 ppb1017 ppb
2005-04-0671 ppb1071 ppb
2005-04-054.2 ppb104.2 ppb
2005-02-2427.3 ppb205.6 to 49 ppb
2005-01-2725.35 ppb204.7 to 46 ppb
2004-12-2133.05 ppb205.1 to 61 ppb
2004-11-1832.6 ppb205.2 to 60 ppb
2004-10-2842.65 ppb204.3 to 81 ppb
2004-09-3077 ppb1077 ppb
2004-09-293.9 ppb103.9 ppb
2004-08-254.2 ppb104.2 ppb
2004-07-294.1 ppb104.1 ppb
2004-06-234 ppb104 ppb
2004-05-264.8 ppb104.8 ppb
2004-04-282.4 ppb102.4 ppb
2004-04-214.23 ppb301 to 9.9 ppb
2004-04-145.9 ppb600.4 to 11 ppb
2004-04-086.72 ppb605.7 to 7.6 ppb
2004-04-072.89 ppb840 to 9.2 ppb
2004-03-244.6 ppb104.6 ppb
2004-02-264.5 ppb104.5 ppb
2004-01-293.2 ppb103.2 ppb