About the Annual BWS Water Quality Report

Each summer, the Water Quality Report from the Board of Water Supply is mailed to all customers. Also known as the Consumer Confidence Report (CCR), it contains a wealth of information about your water quality.


What the Water Quality Report does...

  • Identifies the source that supplies water for your address
  • Reports detected contaminants or elements in the water and ensures that your drinking water meets all safe drinking water standards
  • Describes any treatment process used, if necessary, to make your water safe to drink
  • Explains terms used in the regulation of drinking water
  • Tells you where to go for additional information
girl filling pitcher of water
Water Quality: Frequently Asked Questions site link

Oahu is blessed with water that is among the best quality in the world. What we all do and the habits we practice each day will determine both the quality of our water and the quantity available for our use. Monitoring the quality of our water will not matter if we do not take care of our environment as individuals and as a community.

At the BWS, our job is to make sure it is also the safest. That is why water from each of our sources is regularly tested. We must ensure that Oahu's water supply not only meets the Safe Drinking Water Act requirements, but also exceeds the most demanding regulations governing the quality of our drinking water.

As mandated under Federal and State law, the Hawaii State Department of Health (DOH) and the BWS regularly test Oahu's drinking water for 91 different kinds of chemical "contaminants".

water quality testingBWS conducts about 30,000 tests annually that includes testing approximately 9,000 water samples each year for microbiological contaminants (bacteria). Chlorine is continuously added to our water before it is delivered to our customers to ensure the water does not contain harmful levels of bacteria.

Technically, anything found in water is referred to as a contaminant by the U.S. Environmental Protection Agency (EPA), including natural minerals that enhance its taste and quality. The presence of a contaminant, in itself, does not mean that it is a health risk. It is the amount of a substance in the water that is of most concern.


See Also:
Water Quality Report Summary link to file | Supplemental Report Information link to file

We believe that keeping the public informed about the quality of its drinking water is an important part of our job. Because the health of all Oahu's people depends on safe drinking water, it is truly our most precious possession. Every water user needs to actively participate in the conservation and protection of our water sources.

Regarding Water Hardness

Federal and state law do not require testing for water hardness. Both hard water and soft water are fine for drinking. Water hardness levels do not appear in report. See Water Quality FAQs site link.


GO TO: About the Water Quality Report | Find Your Report

Updated: 06/28/2024