Lead and Drinking Water

The Board of Water Supply (BWS) is required to regularly test water samples from household taps island wide for the presence of lead and copper in accordance with the U. S. Environmental Protection Agency’s (EPA) lead/copper rule.

Although the test results are excellent and have repeatedly shown that lead and copper are not a problem in household drinking water on Oahu, EPA revised the regulations in 2021 to further protect consumers from the impact of lead and copper.

Sources of Lead in Drinking Water

Lead can enter drinking water if service lines or plumbing materials that contain lead corrode. Additionally, if water stands in plumbing systems containing lead for several hours or more, the lead may be more likely to dissolve into your drinking water. For additional information on lead in drinking water provided by the Environmental Protection Agency (EPA), click here external link.

Lead in drinking water is one potential source of lead. Other sources of lead exposure include paint, ceramics, gasoline, batteries, and cosmetics. For more information, click here external link.

Potential Health Effects of Lead

According to the EPA, exposure to lead in drinking water can cause serious health effects in all age groups. Infants and children can have decreases in IQ and attention span. Lead exposure can lead to new learning and behavior problems or exacerbate existing learning and behavior problems. The children of women who are exposed to lead before or during pregnancy can have increased risk of these adverse health effects. Adults can have increased risks of heart disease, high blood pressure, and kidney or nervous system problems.

For more information on the potential health effects of lead, click here external link.

Lead Service Line Inventory

In accordance with the 2021 Lead and Copper Rule Revisions the BWS has developed a service line material inventory that includes information for the entire service line that is connected from our water mains to homes and buildings. The inventory indicates if the material is lead, non-lead, galvanized requiring replacement, or lead status unknown.

To learn more about the materials in the BWS service line that serves your home or business, click here external link.

Testing for Lead and Copper

Using the results of the service line inventory select residential and commercial property sites have been selected for tap water testing for lead and copper. The results of those tests are available by clicking the link below.

Click here external link for the lead and copper sample results.

How You Can Reduce Lead in Drinking Water

The results of our tap water testing show that your water is safe to drink. However, if you are concerned about lead in your drinking water, there are steps you can take to reduce the risk.

Lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. The BWS is responsible for providing high quality drinking water and removing lead pipes, but cannot control the variety of materials used in plumbing components in your home. You share the responsibility by identifying and removing lead materials within your home plumbing and taking steps to reduce your family’s risk.

  • Flush your pipes and run the tap. Before drinking tap water, flush your pipes for several minutes by running your tap, taking a shower, doing laundry of a load of dishes.
  • Use cold water. Use only cold water for drinking, cooking and making baby formula. Hot water may cause increases in lead concentrations at the tap and therefore should not be used to prepare food or baby formula. Boiling water does not reduce or remove lead from drinking water.
  • Use a filter. You can also use a filter certified by an American National Standards Institute accredited certifier to reduce lead in drinking water.
  • Have your water tested. If you are concerned about lead in your drinking water and wish to have your water tested, contact the BWS. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available at http://www.epa.gov/safewater/lead external link.
  • Identify lead-free certification marks on drinking water system and plumbing products. There is a difference between low lead and lead free. The Safe Drinking Water Act reduced the amount of allowable lead content from 8% to 0.25% for pipes, pipe fittings, plumbing fittings, and fixtures and 0.2% for solder and flux. For more information from the EPA, click here external link.

If you are concerned about your child’s potential exposure to lead, you can have your child’s blood tested for lead. Contact your local health care provider or the Hawaii Department of Health for more information.

For More Information

For more information, call us at (808) 748-5041 or email us at contactus@hbws.org. For more information on reducing lead exposure around your home/building and the health effects of lead, visit EPA's Web site at http://www.epa.gov/lead external link or contact your health care provider.


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Updated: 02/21/2024