Waimānalo Beach is a census-designated place located in the City & County of Honolulu, in the District of Koʻolaupoko, on the island of Oʻahu in the U.S. state of Hawaiʻi. This small windward community is located near the eastern end of the island, and the climate is dry. As of the 2020 census, the CDP had a population of 4,823. This neighborhood is clo…Waimānalo Beach is a census-designated place located in the City & County of Honolulu, in the District of Koʻolaupoko, on the island of Oʻahu in the U.S. state of Hawaiʻi. This small windward community is located near the eastern end of the island, and the climate is dry. As of the 2020 census, the CDP had a population of 4,823. This neighborhood is close to, but somewhat separate from Waimānalo, although the two form a single community.