The Power of Information

National Drinking Water Database

Sioux City Water Supply Utilities - Sioux City, IA

Serves 85,028 people


Copper is a naturally occuring metal and drinking water contaminant that enters tap water by corrosion of household plumbing systems and erosion of natural deposits.
This Drinking Water System
Test Days Exceeding Health GuidelinesDefinition of what this is
12 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
16 days
Tests ConductedNumber of individual tests done for this contaminant
60 tests

Testing Summary

Health Limit
Legal Limit

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
CopperCopper is a naturally occuring metal and drinking water contaminant that enters tap water by corrosion of household plumbing systems and erosion of natural deposits.552.95 ppb
1100 ppb
300 ppb
1000 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 Copper

Health Based Limits for Copper

California Public Health GoalsDefined by the State of California Office of Environmental Health Hazard Assessment (OEHHA) as the level of contaminant that is allowed in drinking water. For acutely toxic substances, levels are set at which scientific evidence indicates that no known or anticipated adverse effects on health will occur, plus an adequate margin-of safety. PHGs for carcinogens or other substances which can cause chronic disease shall be based solely on health effects without regard to cost impacts and shall be set at levels which OEHHA has determined do not pose any significant risk to health.300 ppb
National Secondary Drinking Water RegulationsA National Secondary Drinking Water Regulation is a non-enforceable guideline regarding contaminants that may cause cosmetic effects (such as taste, odor, or color). Some states choose to adopt them as enforceable standards. Source: U.S. Environmental Protection Agency. 1000 ppb
Maximum Contaminant Limit Goal (MCLG)A non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.1300 ppb
EPA Human Health Water Quality CriteriaWater quality criteria set by the US EPA provide guidance for states and tribes authorized to establish water quality standards under the Clean Water Act (CWA) to protect human health. These are non-enforceable standards based upon exposure by both drinking water and the contribution of water contamination to other consumed foods. Source: U.S. Environmental Protection Agency.1300 ppb

Testing Results

Testing DateAverage
Samples taken that dayNumber of Non-DetectsRange of Results
2007-09-251100 ppb101100 ppb
2007-09-15555 ppb20470 to 640 ppb
2007-09-07533.33 ppb30150 to 1000 ppb
2007-07-20140 ppb10140 ppb
2007-07-19860 ppb10860 ppb
2007-07-13880 ppb30700 to 1200 ppb
2007-07-121070 ppb20940 to 1200 ppb
2007-07-11570 ppb1520 to 1300 ppb
2007-06-27290 ppb10290 ppb
2007-06-16200 ppb10200 ppb
2004-08-09541.67 ppb6090 to 940 ppb
2004-08-08150 ppb10150 ppb
2004-08-05500 ppb210 to 1000 ppb
2004-08-04395 ppb80100 to 920 ppb
2004-08-03527.27 ppb1110 to 1100 ppb
2004-08-02535 ppb20170 to 900 ppb