| Anahulu River | |
| Pushpin Map: | Hawaii |
| Pushpin Map Caption: | Location of mouth |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | Hawaii |
| Subdivision Type3: | Region |
| Subdivision Name3: | Oahu |
| Length: | 7.1miles |
| Discharge1 Max: | 16200cuft/s |
| Source1: | confluence of Kawainui and Kawaiiki streams |
| Source1 Coordinates: | 21.5786°N -158.0158°W |
| Mouth: | Pacific Ocean |
| Mouth Location: | Waialua Bay |
| Mouth Coordinates: | 21.5944°N -158.1042°W |
| Basin Size: | 16sqmi |
The Anahulu River (also called Anahulu Stream) is a watercourse on the island of Oahu in the U.S. state of Hawaii. It is long.[1] The Hawaiian meaning of the name is ten days.[2]
It is formed on the western side of the northern Koolau Range approximately northeast of Wahiawā by the confluence of Kawainui and Kawaiiki streams, both perennial. It flows west-northwest descending through Kawailoa Gulch, then empties into the eastern end of Waialua Bay at Haleiwa. It has a watershed of approximately and a 100-year peak discharge of 16,200 ft3/s (459 m³/s.
Archaeological evidence indicates that the valley of the river near its mouth was the site of ancient Hawaiian villages. The river valley was abandoned but was later repopulated in the early 19th century, partly as the result of a policy by a King Kamehameha I to grow food to support his military expeditions. The policy included the development of irrigated terraces. In 1832 U.S. Protestant missionaries John Emerson and his wife Ursula Sophia circumnavigated Oahu and put in at the mouth of the river, located at 21.5944°N -158.1042°W. At the village of Haleiwa (from hale (home) of the iwa (frigate bird)), they were welcomed by Chief Laanui and established the Liliuokalani Church in the village.
In the later 19th century the village of Haleiwa and the surrounding river valley became a popular summer vacation destination for the Hawaiian monarchs. The first hotel was built along the river by businessman Benjamin Dillingham, who also built Oahu railroad from Honolulu to the north shore in 1898. The railroad and hotel made the river valley a popular vacation spot.