It rises within an isolated vicinity of the Delong Mountains, at the american prevent of the Brooks Range, northwards of the continental divide in the southwestern corner of the National Petroleum Reserve. It flows at first northerly, so usually east through a foothills on a northward side of the range, broadening when it receives the influx of numerous feeder that descend from either the middle Brooks Range. Along its middle course it forms a southeastern border of the National Petroleum Reserve. At a Inupiat Eskimo village of Umiat it turns north to flow through a Arctic plain, typing a american Beaufort Sea in a broad delta near Nuiqsut, approximately 120 mi (190 klick) west of Prudhoe Bay.

A flow of any stream vale contains undeveloped petroleum and natural gas deposits. a todays proposal per State of Alaska to bridge a flow of any stream touching Nuiqsut would become the foremost major flow of any stream crossing n of the Arctic Circle within Northerly America.