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Water resources of the Lake Superior watershed, northeastern Minnesota

The Lake Superior watershed is mostly a highland, generally 1,200 feet (366 meters) to 2,000 feet (610 meters) above mean sea level. It extends from Duluth to the Canadian border. Both maximum and minimum altitudes for Minnesota occur in the watershed; 2.301 ft (701 ) at Eagle Mountain, about 12 mi (19 km) northwest of Grand Marais, and 602 ft (184 m), the normal level of Lake Superior. Total relief is nearly 1,700 ft (518 m). The North Shore area (Duluth to the Canadian border) has a southeastward slope that is especially precipitous adjacent to Lake Superior. Conforming to this topography, the drainage includes a series of 17 southeastward-flowing streams averaging 23 mi (36 km) in length, with an average gradient from headwaters to mouth of about 57 ft/mi (10.8 m/km). The streams are deeply entrenched and characterized by swift flows, many rapids and waterfalls, and especially steep gradients in the 3 to 5 mi (4.8 to 8.0 km) before entering Lake Superior. The Pigeon River drains the extreme northern part of the watershed and forms the international border between the United States and Canada. More than half of the 610 mi 2 (1580 km 2 ) drainage basin of the Pigeon River lies in Canada. The Nemadji River and tributaries drain the Nemadji Basin, the southern detached part of the watershed. Topographically, the Nemadji Basin is roughly spoon shaped with maximum total relief in Minnesota of about 800 ft (244 m). More than half of the approximately 55-mi (88-km) long river flows northeastward through Wisconsin before reaching Lake Superior.

Minnesota↗

Reconnaissance hydrology of Portage Glacier basin, Alaska

Early reports of conditions in Portage Pass, Alaska, provide evidence that Portage Glacier was formerly larger and thicker. Past conditions, recent history, current retreat, and possible future changes are summarized from an analysis of reports, photographs of the glacier (1939, 1950, and annually since about 1960), and data on snow and ice balance and bathymetry (1972). Between 1900 and 1972, the glacier terminus retreated 3.4 kilometers, and the lower part of the glacier thinned 200 meters. Climatic change controlled the retreat until about 1930; since then deep water at the terminus has influenced the calving retreat. The calving rate and present terminus position cannot be sustained by current climatic conditions and rate of snow accumulation. Thus the glacier will continue to recede until the terminus stabilizes in shallower water, probably about 1.5 kilometers upvalley from the present terminus and in about year 2020, assuming no change in present climatic conditions and calving rate. Possible small climatic changes could cause a shift in the point at which annual snow accumulation equals annual ablation (500 meters) and a corresponding change in terminus behavior. Potential natural hazards include avalanches, outburst floods from ice-dammed lakes, and unstable icebergs.

Alaska↗

Geohydrology of the Cheyenne River Indian Reservation, South Dakota

Effective improvement of economic and social conditions of Indians living on the Cheyenne River Indian Reservation has been hampered by lack of adequate and reliable information about the quantity and quality of water supplies available for development. Compounding the problem is the recent fillinf of Oahe Reservoir, which flooded about 105,00 acres of Indian land, and the consequent relocation of many residents. This report summarizes the results of a water-resources study made at the request of the U.S. Bureau of Indian Affairs. It is intended to provide some of the needed information on water supplies that could be used to alleviate the problems mentioned. The cooperation and courtesy extended by many farmers, ranchers, and residents of the area contributed greatly to the success of the study. Special thanks are due to Mr. John Wall, U.S. Public Health Service, Eagle Butte, and to the personnel of the Land Operations and Conservation Unites of the U.S. Bureau of Indian Affairs, Eagle Butte.

South Dakota↗

Water resources of the St. Louis River watershed, northeastern Minnesota

The St. Louis River is the largest tributary to Lake Superior in Minnesota. It drains a predominantly forested area of about 3,650 mi 2 (Minnesota Department of Conservation, 1959) and discharges into the lake at Duluth. The Mesabi Iron Range, noted for rich deposits of iron ore, parallels much of the northern watershed boundary. Large areas of land were altered by mining activities, as seen on the Landsat-1 MSS 7 images for September 26, 19744 (No. 1795-16203). The northeastward-trending string of water bodies along the northern boundary are flooded mine pits and tailings basins. The northeastern part of the watershed is largely State and National forest, whereas much of the southwestern and central parts are peat-covered wetlands. Generalized topographic features are shown on the map above. The topographic high along the northern boundary includes the Iron Range and is dissected by post-glacial drainage. The most notable drainage gap is that occupied by the Embarrass River. The series of southwestward-trending elongate hills in the eastern part of the watershed, visible on both the Landsat image and the topographic map, is the Toimi Drumlin Field (Wright, 1972). Topographically low, relatively flat land in the southwestern and central parts is a glacial lake plain. St. Louis River gradients are highly variable, being 9 ft/mi from its headwaters to the mouth of Partridge River, slightly more than 1 ft/mi from Partridge River to Cloquet, and 35 to 40 ft/mi in a 15-mi reach below Cloquest. The watershed is sparsely settled except for its northern and south-eastern parts. About 80 percent of the urban population lives on the Iron Range. Most of the suburban and rural residents alro live on or near the range or in the southeastern part of the watershed. Total population (1970), exclusive of those in the city of Duluth, which is included in the Lake Superior watershed (Olcott and others, 1976), was about 117,000.

Minnesota↗

Floods at Mount Clemens, Michigan

The approximate areas inundated during the flood of April 5-6, 1947, by Clinton River, North Branch and Middle Branch of Clinton River, and Harrington Drain, in Clinton Township, Macomb County, Mich., are shown on a topographic map base to record the flood hazard in graphical form. The flood of April 1947 is the highest known since 1934 and probably since 1902. Greater floods are possible, but no attempt was made to define their probable overflow limits. The Clinton River Cut-Off Canal, a flood-relief channel which diverts flow directly into Lake St. Clair from a point about 1500 feet downstream from Gratiot Avenue (about 9 miles upstream from the mouth) has been in operation since October 1951. The approximate limits of overflow that would results from a flood equivalent in discharge to that of April 1947, and occurring with the Cut-Off Canal in operation, are also shown. Although the Cut-Off Canal may reduce the frequency and depth of flooding it will not necessarily eliminate future flooding in the area. Improvements and additions to the drainage systems in the basin, expanding urbanization, new highways, and other cultural changes may influence the inundation pattern of future floods. The preparation of this flood inundation map was financed through a cooperative agreement between Clinton Township, Macomb County, Mich., and the U.S. Geological Survey. Backwater curves used to define the profile for a hypothetical flood on the Clinton River downstream from Moravian Drive, equivalent in discharge to the 1947 flood, but occurring with the present Cut-Off Canal in operation; flood stage established at the gaging station on Clinton River at Mount Clemens; and supplementary floodmark elevations were furnished by the Corps of Engineers. Bench-mark elevations and field survey data, used in the analysis of floods on Harrington Drain, were furnished by the Macomb County Drain Commission.

Michigan↗