Waimānalo is a census-designated place (CDP) in the City & County of Honolulu, in the District of Koʻolaupoko on the island of Oʻahu, Hawaii, United States. This small windward community is located near the eastern end of the island. In the Hawaiian language Waimānalo means "potable water"; it is so named for the many brackish ponds in the area that were used for irrigation. As of the 2010 Census, the CDP had a population of 5,451.