Ala Wai Canal, Major drainage canal in Waikiki, Honolulu, United States.

The Ala Wai Canal is an artificial waterway running roughly 2 miles along the northern edge of Waikiki, collecting water from multiple streams in central and eastern Honolulu before emptying into the Pacific Ocean. The canal is crossed by several bridges and bordered by walking paths that follow its entire length through the urban landscape.

The canal was constructed between 1921 and 1928 by Hawaiian Dredging Construction Company under Walter F. Dillingham's leadership to convert Waikiki's swamplands into developable land. This engineering project transformed the area from wetlands into the modern urban and tourist center it is today.

The canal's name, Ala Wai, means "pathway of water" in Hawaiian. The Ala Wai Promenade, a linear park along the northwest bank, was built together with the canal and is used for walking, jogging and fishing; fishing from the banks has been a pastime since the waterway opened.

Main access points with walking paths and bridges are located at McCully Street, Kalakaua Avenue, and Ala Moana Boulevard, making the waterway easy to explore on foot. Paths run along the entire length of the canal, though shade is limited during midday hours in the tropical sun.

The canal was designed with two outlets, one at each end, so sediment could flush into the ocean. Engineers skipped the eastern outlet near Kapiʻolani Park and the Waikiki Natatorium, fearing contamination would settle on Waikiki Beach. The canal has been dredged at least three times, in 1967, 1978 and 2002.