Lead & CCWD Drinking Water

The United States Environmental Protection Agency has been working closely with water agencies across the nation to update and improve rules concerning the amount of lead in drinking water. Lead was commonly used in older household plumbing materials and some water service lines.

None of the water service pipelines used by the Contra Costa Water District contain lead. Within CCWD, the greatest chance for exposure to lead is from the pipes and fixtures used in older homes, usually those built before 1986 when plumbing rules changed.

Lead in drinking water can cause a variety of adverse health effects. In babies and children, exposure to lead in drinking water above the action level can result in delays in physical and mental development, along with slight deficits in attention span and learning abilities. In adults, it can cause increases in blood pressure. Adults who drink water containing lead over many years could develop kidney problems or high blood pressure.

Homes built before 1986 are more likely to have lead pipes, fixtures and solder. New homes are also at some risk. Legally "lead-free" plumbing may contain up to 0.25% lead. The most common problem is with brass or chrome-plated brass faucets and fixtures which can leach significant amounts of lead into the water, especially hot water.

How to Reduce Lead in Drinking Water at Home

Flush your pipes before drinking and only use cold water for consumption. The more time water has been sitting in your home's pipes, the more lead it may contain. Any time water in a particular faucet has not been used for six hours or longer, "flush" your cold-water pipes by running the water until it becomes as cold as it will get.

Use only water from the cold-water tap for drinking, cooking, and especially for making baby formula. Hot water is likely to contain higher levels of lead.

These two recommendations are very important to the health of your family. They will probably be effective in reducing lead levels because most of the lead in household water usually comes from the plumbing in your house. Here is a guide to reducing lead in your drinking water. 


Some commercial water filters claim to remove lead from water. Please check the package to make sure the filter is certified to meet NSF Standard 53 for removing the contaminant “lead” before buying one of these filters. NSF International has created a guide that lists all NSF-certified filters for lead reduction in drinking water.

How to Tell if Your Water Contains Too Much Lead

Since you cannot see, taste, or smell lead dissolved in water, testing is the only sure way of telling whether there are harmful quantities of lead in your drinking water. You should be particularly suspicious if your home has lead pipes (lead is a dull gray metal that is soft enough to be easily scratched with a house key), or if you see signs of corrosion (frequent leaks, rust-colored water, stained dishes or laundry).

You may wish to have your water tested for lead by a laboratory. There are several local labs that test water for lead. These include:

  • Cerco Analytical 925-462-2771
  • Eurofins  800-985-5955
  • McCampbell Analytical 925-252-9262
  • Test America at 949-261-1022.

Water Quality Testing Program

CCWD tests every three years for lead in more than 50 pre-selected homes from throughout the treated water service area.  These tests are done on homes with older plumbing.  Results are published in the Annual Water Quality Report.  Between 2000 and 2005, the District tested 324 homes and only two homes were found to have lead levels that exceeded the EPA minimums. 

CCWD completed its latest round of Lead and Copper Rule monitoring in June 2016. Results shown in the table below are in full compliance with federal and state standards and are well below the EPA’s action level. CCWD’s corrosion control efforts are effective and are
demonstrated by these results: 




Sample Event

June 2016

June 2016


<0.0005 – 0.008

0.011 – 0.34

90th Percentile*



Detection Limit For Reporting**



EPA Action Level



Number of Samples Collected



Number Sites Above Method Reporting Limit



Number Sites Above DLR



Number Sites Above Action Level



*  90th Percentile: 90 percent of the samples are less than or equal to the value presented. This value is used to measure compliance with the US Environmental Protection Agency (EPA) Action Level.

**  Detection Limits for Purposes of Reporting (DLRs) are set by the California State Water Resources Control Board - Division of Drinking Water (DDW). When a contaminant is found below the DLR, it is considered non-detect (ND) for the purposes of reporting.


We realize that any amount of lead in water may cause concern for some. CCWD, therefore, is providing guidance on how to reduce lead in your drinking water.

For more information on lead in drinking water please send an email or call our Water Quality Hotline at 925-688-8156.