The Power of Information

National Drinking Water Database

City of Raleigh Public Utilities Department Utilities - Raleigh, NC

Serves 409,542 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
0 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)
0 days
Test DaysNumber of days in which this chemical has reported results in the data we received from the State
28 days
Tests ConductedNumber of individual tests done for this contaminant
52 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.35.33 ppb
140 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
2005-09-2330 ppb1030 ppb
2005-09-2260 ppb2040 to 80 ppb
2005-09-13140 ppb10140 ppb
2005-09-0710 ppb1010 ppb
2005-09-02106.67 ppb3020 to 220 ppb
2005-08-210 ppb110 ppb
2005-08-18140 ppb10140 ppb
2005-08-1220 ppb1020 ppb
2005-08-110 ppb110 ppb
2005-08-0530 ppb2020 to 40 ppb
2005-07-1515 ppb210 to 30 ppb
2005-07-1425 ppb210 to 50 ppb
2005-07-130 ppb110 ppb
2005-07-120 ppb110 ppb
2005-07-110 ppb110 ppb
2005-07-0660 ppb1060 ppb
2005-07-0530 ppb310 to 80 ppb
2005-06-2947.5 ppb410 to 80 ppb
2005-06-2833.33 ppb3010 to 70 ppb
2005-06-2716.67 ppb620 to 40 ppb
2005-06-2610 ppb1010 ppb
2005-06-2510 ppb210 to 20 ppb
2005-06-2445 ppb2030 to 60 ppb
2005-06-2350 ppb510 to 120 ppb
2005-06-2210 ppb1010 ppb
2005-06-2150 ppb1050 ppb
2005-06-2040 ppb1040 ppb
2005-06-1810 ppb1010 ppb