EPA SDWIS DataCalifornia

Copper in California Drinking Water

California has 20,579 public water systems. 569 have recorded copper violations.

Total Systems

20,579

With Violations

569

EPA MCL

1.3

Population Served

42.7M

Copper in California: Key Facts

Total Water Systems

20,579

Systems with Violations

569

Lead Violations

142

Copper Violations

569

EPA Standard

1.3 mg/L

MCLG (goal): 1.3 mg/L

Systems with Copper Violations in California

SystemPopulationViolations
ALAMEDA COUNTY WATER DISTRICT344K9
SANTA ROSA, CITY OF175K4
CORONA, CITY OF169K36
SANTA CLARITA VALLEY W.A.-SANTA CLARITA135K9
CITY OF ANTIOCH115K6
SOUTH TAHOE PUD - MAIN100K13
DUBLIN SAN RAMON SERVICES DISTRICT99K4
SANTA CRUZ WATER DEPARTMENT95K15

Health Effects of Copper Exposure

Gastrointestinal distress

Nausea, vomiting, and diarrhea at high levels

Liver and kidney damage

Chronic high exposure can damage organs

Wilson's disease risk

Those with Wilson's disease are especially sensitive

Short-term: gastrointestinal distress. Long-term: liver or kidney damage. People with Wilson's disease are more sensitive.

Frequently Asked Questions

Is there copper in California water?

California has 20,579 public water systems. 569 have recorded copper violations based on EPA SDWIS data. If you are on a private well, your water is not covered by these regulations and should be tested independently.

How can I check my California water for copper?

Search for your water system using the WaterCheck system lookup, or contact your utility and request a copy of your Consumer Confidence Report (CCR). The CCR is published annually and lists all detected contaminants, their levels, and the EPA MCLs. For private wells, contact a state-certified lab for independent testing.

What is the EPA limit for copper?

The EPA Maximum Contaminant Level (MCL) for copper is 1.3 mg/L. Systems that exceed MCLs are required to notify customers and take corrective action.

Copper at a Glance

Categoryheavy metal
EPA MCL1.3 mg/L

Source

Corrosion of household plumbing; erosion of natural deposits; leaching from wood preservatives

How to Filter Copper

  • +Run cold water 30 seconds to 2 minutes before use
  • +NSF/ANSI 53 certified filters can reduce copper
  • +Avoid letting water sit in copper pipes overnight