Hydrologic reconnaissance of the Noatak River basin, Alaska, 1978

Abstract

Hydrologic data were collected in 1978 described water resources of the Noatak River basin, Alaska. Streamflow varies seasonally. No flow was observed from the upper part of the basin in late winter (April). In the lower part of the basin springs support perennial flow in the Kugururok River and downstream along the Noatak. The discharge of the Noatak was 150 cubic feet per second in April 1978. During the summer, rainstorms are common, and runoff produces high flow. During August 1978, flow was normal in the basin; unit runoff averaged about 1 cubic foot per second per square mile. The Noatak is a gravel-bed stream of moderate slope. It drops about 1,800 feet in elevation from a point near the head waters to the mouth, a distance of 400 miles. Streambed material in most places is gravel, cobbles, and boulders, maximum riffle depths and pool widths increase in a downstream direction. Stream velocity in August 1978 increased from about 1 foot per second in the upper basin to about 4 feet per second in the lower reaches. High-water marks of the maximum evident flood were found at elevations from bankfull to 5 feet above bankfull. Maximum evident flood unit runoff rates were estimated to be less than 50 cubic feet per second per square mile. Scars produced by ice jams were seldom seen above bankfull. Bank erosion appears to be most active in the lowlands. Water in the Noatak River basin is virtually unaffected by man 's activity. Water quality varies with location, weather, season, and source; the water is normally clear, cool, and hard. During late winter sea water intrudes into the Lower Noatak Canyon. Benthic invertebrate community composition and variability suggest the river 's undiminished natural quality. (USGS)