Yes, it is safe to drink and use tap water on the island of Oʻahu including in Waikīkī.
The Board of Water Supply in Hawaiʻi works in conjunction with State and Federal agencies, such as the U.S. Environmental Protection Agency and Hawaiʻi State Department of Health, to ensure the water in Hawaiʻi is safe to drink.
Note, fluoride is not added to the water supply in Hawaiʻi (only on military installations). Hawaiʻi’s water supply is chlorinated, but only enough chlorine is added to keep disease-causing bacteria from contaminating the system. The pH balance of Hawaiʻi’s drinking water occurs naturally between 7 to 8, it ranges from being neither acidic nor alkaline (pH7) to being slightly alkaline (pH8).
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