Kōloa is an unincorporated census-designated place in Kauaʻi County, Hawaiʻi, United States. The first successful sugarcane plantation in the Islands was started here in 1835. It became a part of Grove Farm in 1948. The population was 1,942 at the 2000 census. Kōloa is often incorrectly translated as native duck, which is the correct translation for the similar-looking koloa. Kōloa has no known translation. According to one account, the district Kōloa was named for a steep rock called Pali-o-kō-loa which was found in 'Waikomo' stream.