The Power of Information

National Drinking Water Database

Crystal Lake Utilities - Crystal Lake, IL

Serves 40,634 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
10 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
24 days
Tests ConductedNumber of individual tests done for this contaminant
62 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.276.64 ppb
903 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
2008-11-180 ppb110 ppb
2008-07-080 ppb110 ppb
2008-06-2530 ppb1030 ppb
2008-06-24308 ppb10308 ppb
2008-06-20903 ppb10903 ppb
2008-06-180 ppb110 ppb
2008-06-17175 ppb10175 ppb
2008-06-13458 ppb30148 to 692 ppb
2008-06-12291 ppb710 to 837 ppb
2008-06-11451 ppb8033 to 1340 ppb
2008-06-10656 ppb20628 to 684 ppb
2008-06-09185.5 ppb2077 to 294 ppb
2008-06-06477 ppb30387 to 595 ppb
2005-08-02830 ppb10830 ppb
2005-07-22395 ppb20360 to 430 ppb
2005-07-12140 ppb10140 ppb
2005-07-07160 ppb10160 ppb
2005-06-23472.5 ppb410 to 1400 ppb
2005-06-2258 ppb530 to 160 ppb
2005-06-200 ppb110 ppb
2005-06-17243.33 ppb310 to 570 ppb
2005-06-16100 ppb620 to 190 ppb
2005-06-15306 ppb50110 to 490 ppb
2005-06-140 ppb110 ppb