Cook Inlet

Cook Inlet (Denaʼina: Tikahtnu; Sugpiaq: Cungaaciq) stretches 180 miles (290 km) from the Gulf of Alaska to Anchorage in south-central Alaska. Cook Inlet branches into the Knik Arm and Turnagain Arm at its northern end, almost surrounding Anchorage. On its southern end, it merges with the Shelikof Strait, Stevenson Entrance, Kennedy Entrance and Chugach Passage. The Cook Inlet and both its arms are bodies of brackish water, containing a turbid mix of ocean salt-water and freshwater runoff from the various rivers and streams. The narrow channel of the inlet funnels the tides creating very fast-moving currents, rip tides, and occasional bore tides. Cook Inlet watershed is the most populated watershed in Alaska. The watershed covers about 100,000 km2 (39,000 sq mi) of southern Alaska, east of the Aleutian Range, south and east of the Alaska Range, receiving water from its tributaries, which include the Knik River, the Little Susitna River, the Susitna and Matanuska rivers, Eagle River, Ship Creek, Resurrection Creek, Portage Creek, Kenai River, and many others. The watershed includes the drainage areas of Denali and is the collection point for the runoff from many surrounding glaciers, leading to the high turbidity and large silt deposits. Within the watershed there are several national parks and the active volcano Mount Redoubt, along with three other historically active volcanoes. Cook Inlet provides navigable access to the port of Anchorage at the northern end, and to the smaller Homer port further south. Before the growth of Anchorage, Knik was the destination for most marine traffic in upper Cook Inlet. Approximately 400,000 people live within the Cook Inlet watershed.