The Power of Information

National Drinking Water Database

Ledyard Wpca, Sablewoods System Utilities - Waterford, CT

Serves 220 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
17 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
27 days
Tests ConductedNumber of individual tests done for this contaminant
40 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.473.43 ppb
1350 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
2007-10-31211 ppb10211 ppb
2007-10-30604 ppb20588 to 620 ppb
2007-10-19241 ppb20200 to 282 ppb
2007-10-17521 ppb10521 ppb
2007-10-16402.25 ppb40238 to 824 ppb
2007-05-1683 ppb1083 ppb
2007-04-12256 ppb10256 ppb
2007-04-10278 ppb30227 to 358 ppb
2007-03-22258.5 ppb20191 to 326 ppb
2007-03-21437.5 ppb20292 to 583 ppb
2007-03-2084 ppb1084 ppb
2006-11-29586.67 ppb30140 to 1080 ppb
2006-11-20713 ppb10713 ppb
2006-11-15233 ppb10233 ppb
2006-11-14342 ppb10342 ppb
2006-11-10837 ppb10837 ppb
2006-10-281000 ppb101000 ppb
2006-10-25378 ppb10378 ppb
2006-10-24730 ppb10730 ppb
2006-04-25150 ppb10150 ppb
2006-04-14450 ppb10450 ppb
2006-04-13163 ppb10163 ppb
2006-04-12527 ppb10527 ppb
2006-04-07480 ppb10480 ppb
2006-03-13386.67 ppb30300 to 533 ppb
2006-03-101080 ppb101080 ppb
2006-03-071350 ppb101350 ppb