Water availability, quality, and use in Alaska

Abstract

The Alaska Water Assessment, sponsored by the Water Resources Council, is a specific problem analysis for Alaska of the National Assessment of Water and Related Land Resources. The assessment addresses water and water-related land problems, present and future. It was felt that a supplementary report, as a part of the assessment, was needed to state in general terms the present hydrologic conditions, including the availability, quality, and use of both surface water and ground water in the Alaska region. Alaska covers an area of 586,412 square miles, about one-fifth of the total area of the United States. Characteristic of parts of the region is the presence of permafrost. The physiography of Alaska ranges from low coastal plains of the Arctic and deltas of the major rivers to peaks of the Alaska Range. Climate in the State ranges from the maritime rain forests of southeast Alaska to the frozen desert of the Arctic. Mean annual runoff for the region is estimated at 1,260,000 cubic feet per second which includes an estimated 163,000 cubic feet per second of inflow from Canada. The Alaska region has been divided into six hydrologic subregions and eighteen subareas. For each subarea, estimated mean annual runoff per square mile, suspended-sediment concentrations that can be expected during "normal" summer runoff and, where data are available, flood magnitudes and frequencies are illustrated on maps. Also illustrated are estimated ground-water yields in each subarea. Tables listing water quality of both ground water and surface water from selected wells and streams are also included. Water use according to the type of use is discussed, and estimates are given for the amounts used. Water-use categories in the State include domestic, irrigation, livestock, seafood processing, oil and gas development, petrochemical processing, pulp mills, hydroelectric, coal processing, steam electric, mineral processing, sand and gravel mining, and fish-hatchery operations. Also illustrated on maps are estimated ground-water yields in each subarea. Tables listing water quality of both ground water and surface water from selected wells and streams are also included.