The 75 mile long Matanuska River originates in the Chugach Mountains at the Matanuska Glacier and drains southwesterly into Knik Arm, an extension of Cook Inlet, before joining the Gulf of Alaska. The river valley is a wide sandur plain: glacial till deposited by melt-waters of the receding glacier. This is typical of glacier fed river valleys in Alaska. The river meanders on this flood plain but is capable of covering the valley floor during periods of high flow. The Matanuska river watershed is 2,070 square miles in size.
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait. Approximately half of Alaska's 710,231 residents (as per the 2010 United States Census) live within the Anchorage metropolitan area. Alaska is the least densely populated state of the U.S.Source: http://en.wikipedia.org/wiki/Alaska