Hydrologic reconnaissance of the Noatak River basin, Alaska, 1978

Abstract

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.

Magnitude and frequency of floods in Alaska and conterminous basins of Canada

“…If large floods have occurred in the recent past (within the last 50 years), floodmarks are usually evident (Childers and Kernodle, 1981). Maximum evident floods in Alaska determined by Childers (1974), Childers and others (1979), Childers and Kernodle (1981), and Kernodle and others (1983) are shown on table 6.…”

Reconnaissance of surface-water resources in the Togiak River basin, southwestern Alaska, 1980 and 1982

“…MEF marks were found at most sites but were scarce compared to sites previc (Childers and Kernodle, 1981). Backwater from usly surveyed in northern Alaska lake stages resulting from winddriven waves affected sites 1, 4, and 5 near the ;inlets to the Togiak Lakes so that MEF discharges could not be determined.…”

“…The highest such flood signs along a channel are indications of "maximum evident floods" (MEF's). If large floods have occurred in the recent past (within the last 50 years), floodmarks are usually evident (Childers and Kernodle, 1981). If there is no such evidence, then it is probable that no significant flood has occurred recently.…”

Overview of environmental and hydrogeologic conditions at Kotzebue, Alaska

“…In general, rivers and streams in northwestern Alaska will reach their maximum flows during the spring snowmelt period and will have secondary peak flows following heavy rainfall during the summer. Many streams, including the upper tributaries and headwater reaches of the Noatak and the Kobuk Rivers, approach zero flow during the long cold winter (Childers andKernodle, 1981, 1983). …”

“…These data-collection sites, near the villages of Noatak and Kiana, are about 30 km north and 90 km east of Kotzebue, respectively. The quality of the Noatak and Kobuk Rivers was investigated at a reconnaissance level during 1978-80 (Childers andKernodle, 1981, 1983). The quality of the water, indicated by the chemical analyses and macroinvertebrate communities, generally was excellent.…”