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C. E. Sloan

Publications and source records attributed to C. E. Sloan.

6 recordsLinked to original sources
USGS1986

Effect of glacier ablation on the Snettisham Hydroelectric Project, Long Lake and Crater Lake basins, Alaska, with a section on streamflow records

Long Lake Basin in the Snettisham Project Area southeast of Juneau, Alaska, yields water used for the production of hydroelectric power. Development of adjacent Crater Lake is planned to increase the Project 's generating capacity. Estimates of the hydroelectric potential of the lakes are based on streamflow records which are influenced by glaciers that cover 25% of the combined basins. Analysis of streamflow records shows that the quality and extent of records in the area are sufficient to predict flow from the Crater Creek basin with a fairly high degree of confidence. Comparison of aerial photographs indicates that glacier ablation and recession have been continuous since at least 1929. Estimates of ice-volume change from photogrammetric measurements indicate that less than 2.5% of the average runoff from the basins of Long and Crater Lakes has been from reduction in glacier-ice storage. (Author 's abstract)

Alaska↗
USGS1986

Hydrologic reconnaissance of the Unalakleet River basin, Alaska, 1982-83

The Unalakleet River, Alaska, from its headwaters to the confluence of the Chiroskey River has been designated as a wild river and is included in the National Wild and Scenic Rivers System. Yearly low flow, which occurs during the winter, is sustained by groundwater discharge; there are few lakes in the basin and the cold climate prevents winter runoff. The amount of winter streamflow was greatest in the lower parts of streams with the exception of the South River and was apparently proportional to the amount of unfrozen alluvium upstream from the measuring sites. Unit discharge in late winter ranged from nearly zero at the mouth of the South River to 0.24 cu ft/sec/sq mi in the Unalakleet River main stem below Tenmile River. Summer runoff at the time of the reconnaissance may have been slightly higher than normal owing to recent rains. Unit runoff ranged from a low of 1.0 cu ft/sec/sq mi at the South River, to a high value of 2.4 cu ft/sec/sq mi at the North Fork Unalakleet River. Flood marks were present in the basin well above streambank levels but suitable sections to measure the maximum evident flood by slope-area methods were not found. Flood peaks were calculated for the Unalakleet River and its tributaries using basin characteristics. Calculated unit runoff for the 50-year flood ranged from about 17 to 45 cu ft/sec/sq mi. Water quality was good throughout the basin, and an abundant and diversified community of benthic invertebrates was found in samples collected during the summer reconnaissance. Permafrost underlies most of the basin, but groundwater can be found in unfrozen alluvium in the stream valleys, most abundantly in the lower part of the main tributaries and along the main stem of the Unalakleet River. Groundwater sustains river flow through the winter; an estimate of its quantity can be found through low-flow measurements. Groundwater quality in the basin appears to be satisfactory for most uses. Currently, little groundwater is used within the basin. The water supply for Unalakleet is obtained from a well and gallery in a small valley north of the airport, outside the Unalakleet River basin. (Author 's abstract)

Water-Resources Investigations Report↗
USGS1986

Digital data base of lakes on the North Slope, Alaska

The National Mapping Division and Water Resources Division of the U.S. Geological Survey have produced a digital data base of approximately 23,330 lakes on the North Slope of Alaska. The inventoried region consists of the area north of the 69th parallel and is composed of sixteen 1° x 3° quadrangles. The data base includes (1) locations of lake centers in latitude and longitude, (2) a unique number for each lake within a quadrangle, and (3) acreage for water classes (deep, shallow or turbid, and ice) within each lake and lake total. The digital data base is an easily accessible storage and retrieval system that will allow for rapid identification of a particular lake or region of lakes and its characteristics. The data base is designed to accommodate field study data such as lake depth, water quality, volume of water, ice thickness, and other pertinent information.

Water-Resources Investigations Report↗
USGS1977

Hydrologic reconnaissance of the eastern North Slope, Alaska, 1975

The part of the Arctic coast of Alaska between the Colville River and the Canadian boundary was visited in April, August, and November 1975. The study area is characterized by its cold climate and is largely uninhabited, but oil and gas discoveries have spurred development of parts of the area. Sensible, coordinated development requires information about water resources. The purpose of the April reconnaissance was to locate winter streamflow and describe its quantity and quality. A followup summer trip was made in August to determine the flood characteristics of selected streams by measuring channel geometry in relation to bankfull discharge and the maximum evident flood and by estimating channel roughness. In addition, one lake was sampled, the discharge of a few springs was measured, and samples of spring water were taken. Because streamflow in August was assumed to be representative of normal summer flow, water quality was examined in streams for which flood surveys had been made. Samples of aquatic invertebrate populations were taken from most sites on the April and August trips. Another reconnaissance trip from Prudhoe Bay east to Canada was made in November to measure discharge in selected streams and springs, to measure ice thickness and water depth in selected lakes, and to collect water samples for water-quality analyses. Tables of data, photographs, and maps are included. (Woodard-USGS)

Alaska↗
USGS1972

Ground-water hydrology of prairie potholes in North Dakota

Prairie potholes (sloughs) are water-holding depressions of glacial origin in the prairies of the Northern United States and southern Canada. Water is supplied to the potholes by precipitation on the water surface, basin runoff, and seepage inflow of ground water. Depleticn of pothole water results from evapotranspiration, overflow, and seepage outflow. Since potholes generally do not overflow, seepage outflow is the principal way in which dissolved salts can be removed. Salinity of pothole water is therefore a good indication of the seepage balance. Net seepage outflow results in fresh to brackish waters that constitute ephemeral to semipermanent ponds, whereas net seepage inflow results in brackish to saline waters that constitute semipermanent to permanent ponds. Because the water table in the glacial deposits is continuous with the water surface in prairie potholes, the watertable gradient is adjusted to the water-surface elevation of the potholes. In cross section the water table is represented by a nearly straight line which connects potholes. The configuration of the water table around a pothole determines the direction of ground-water flow with respect to the pothole. Ground water flows toward the pothole if the adjacent water table is higher than the pothole water surface and flows away from the pothole if the adjacent water table is lower than the pothole water surface. Prairie potholes were studied in North Dakota on the Coteau du Missouri, an area of stagnation moraine. About 90 percent of the glacial drift on the Coteau du Missouri is glacial till, and the remainder is largely glacial outwash and lake sediments. Ground-water movement in glacial till is controlled by its lithology and structure. This till, being a poorly sorted, largely unstratified mixture of clay, silt, sand, and gravel, is not highly permeable, so ground water moves most readily along the joints. Because joints in glacial till are most numerous near the land surface (owing to weathering effects), the most active ground-water flow systems are shallow and localized in the vicinity of potholes. As a result, local ground-water flow systems have a noticeable effect on pothole hydrology, particularly the salinity

Professional Paper↗