Waimānalo is a census-designated place (CDP) in the District of Koʻolaupoko, in the City & County of Honolulu, on the island of Oʻahu, Hawaii, United States. This small windward community is near the eastern end of the island. Waimānalo means "potable water"; it is so named for the many brackish ponds in the area that were used for irrigation. As of the 2020 census, the CDP had a population of 6,057.