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A reconnaissance-level study of the water resources of the Noatak River basin was made in April (late winter) and August (late summer) of 1978. The major purpose of the study was to evaluate the quantity and quality of the surface-water resource. Streamflow varies seasonally. No flow was observed from the upper part of the basin in late winter (April). However, in the lower part of the basin springs support perennial flow in the Kugururok River and downstream along the Noatak River. The discharge of the Noatak River was 150 cubic feet per second in April 1978. During the summer, rainstorms are common, and runoff produces high flow. During August 1978, unit runoff averaged about 1 cubic foot per second per square mile, which would be normal for runoff at the discontinued streamgaging station, Noatak River at Noatak. 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 depth and pool width increase in a downstream direction. Stream velocity also increases downstream. Velocity measured in August 1978 ranged from about 1 foot per second in the upper basin, to 4.5 feet per second in the Grand Canyon of the Noatak. 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 rarely 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. The composition and variability of the benthic invertebrate community suggest the river's undiminished natural quality. Water quality varies with location, weather, season, and source; the water is ordinarily clear, cool, and hard. During late winter, sea water intrudes into the Lower Noatak Canyon.

The streamflow-data program in Alaska was analyzed to design a better data network. The analysis included (1) definition of the goals of the streamflow-data program, (2) evaluation of the available data to see which goals have already been achieved, and (3) consideration and recommendation of future programs to achieve the goals that have not been met. It was found that few of the goals have been met. Many new gaging stations are proposed to provide data to reach remaining unmet goals. Also, other kinds of data collection are proposed to complement the gaging-station data to attain the goals.

Repeated site surveys and aerial photographs at 26 stream crossings along the trans-Alaska pipeline system (TAPS) route during the period 1969-74 provide chronologie records of channel changes that predate pipeline-related construction at the sites. The 1974 surveys and photographs show some of the channel changes wrought by construction of the haul road from the Yukon River to Prudhoe Bay and by construction of camps and working pads all along the pipeline route. No pipeline crossings were constructed before 1975. These records of channel changes together with flood and icing measurements are part of the United States Department of the lnterior•s continuing surveillance program to document the hydrologic aspects of the trans-Alaska pipeline and its environmental impacts. Because the pipeline route crosses and lies within many stream channels, one of the obvious hydrologic hazards is channel erosion. It was considered a major hazard by R. F. Hadley and G. C. Lusby (written commun., 1969) after a short reconnaissance of the proposed route, and also by the U.S. Water Resources Council in a national assessment of water resources (1968). The Department of the Interior has also recognized the channel erosion problems in considering the environmental impacts of TAPS and has stipulated conditions for their control (U.S. Department of the Interior, 1972a, b, c). The Alyeska Pipeline Service Company, which is to build and operate TAPS, has described methods for complying with the Department of the lnterior•s stipulations for channel and erosion control (Alyeska Pipeline Service Co., written commun., project description, 3 volumes of text and 20 appendix vo 1 umes, 1971). Two basic channel erosion problems are: (1) erosion that could be severe enough to cause pipeline rupture and oil spillage, and (2) erosion that could cause water-quality changes through increased concentration of suspended sediment. Erosion that could endanger the

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