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Perry G. Olcott

Publications and source records attributed to Perry G. Olcott.

7 recordsLinked to original sources

Ground Water Atlas of the United States: Segment 12, Connecticut, Maine, Massachusetts, New Hampshire, New York, Rhode Island, Vermont

The State of New York and the six New England States of Maine, Vermont, New Hampshire, Massachusetts, Connecticut, and Rhode Island compose Segment 12 of this Atlas (fig. 1). The seven States have a total land area of about 116,000 square miles (table 1); all but a small area in southwestern New York has been glaciated. Population in the States of Segment 12 totals about 30,408,000 (table 1) and is concentrated in southern and eastern Massachusetts, Connecticut, Rhode Island, and especially New York (fig. 1). The northern part of the segment and the mountainous areas of New York and much of New Hampshire, Vermont, and Maine are sparsely populated. The percentage of population supplied from ground-water sources during 1980 was 54 to 60 percent in Maine, New Hampshire, and Vermont (table 1). Nearly all rural, domestic, and small-community water systems obtain water from wells that are, in comparison with other sources, the safest and the least expensive to install and maintain. Where water demand is great-in the urban areas of New York, Connecticut, Massachusetts, and Rhode Island-sophisticated reservoir, pipeline, and purification systems are economically feasible and are needed to meet demands. Surface water is the principal source of supply in these four States, and ground water was used to supply only 24 to 35 percent of their population during 1980 (table 1).

Connecticut, Maine, Massachusetts, New Hampshire, ↗

Ground Water Atlas of the United States: Segment 9, Iowa, Michigan, Minnesota, Wisconsin

Segment 9, which consists of Minnesota, Iowa, Wisconsin, and Michigan, abuts the Canadian border in the upper Midwest and lies adjacent to or surrounds four of the Great Lakes-Superior, Michigan, Huron, and Erie. Thousands of small to large lakes similar to the one shown in figure 1 dot the landscape, which is drained by numerous rivers and streams tributary primarily to the Mississippi River in the west and to the Great Lakes-St. Lawrence River system in the east. These abundant surface-water sources represent an ample supply of water to large users, such as the cities of Milwaukee, Wis., and Detroit, Mich. However, water stored in unconsolidated and consolidated sedimentary-rock aquifers that underlie the four States also is in abundant supply and is an economical source that can be used for nearly any purpose, usually with little or no treatment. In more than 95 percent of the four-State area, these aquifers supply water to a broad spectrum of consumers-from individual households to cities, such as St. Paul, Minn., Madison, Wis., and Lansing, Mich. These aquifers are the subject of this chapter. The geology and the hydrology of each of the principal aquifers are illustrated and discussed insofar as information was available from the literature. Hydrogeology, ground-water flow, availability and quality of water, and freshwater withdrawals from each of the aquifers are the principal subjects of discussion. Population in the four States is concentrated in the cities and is thinly dispersed in the broad agricultural areas of the States (fig. 2). Minneapolis-St. Paul, Minn., Des Moines, Iowa, Milwaukee and Madison, Wis., and Detroit and Lansing, Mich., are a few of the principal cities. Many of these cities and other large population centers represent areas of concentrated ground-water withdrawals. Precipitation is the source of all water in Segment 9. Average annual precipitation ranges from about 20 to 40 inches across the segment and generally increases from northwest to southeast (fig. 3). Precipitation is least in the northwestern part of the segment because of the orographic effect of the Rocky Mountains, which are hundreds of miles to the west. Annual precipitation in excess of 36 inches that falls south and east of Lakes Superior and Michigan (fig. 3) is a result of the prevailing westerly winds that evaporate moisture from the lakes; this moisture subsequently condenses and falls as precipitation over the land. Average annual runoff in rivers and streams (fig. 4) generally reflects average annual precipitation patterns (fig. 3). Runoff generally increases from less than 1 to more than 20 inches. Runoff also tends to be substantial downwind from Lakes Superior and Michigan. However, in no part of the segment does runoff exceed precipitation. Much of the water from precipitation is returned to the atmosphere by evapotranspiration-evaporation from the land and water surfaces, and transpiration by plants. Some of the water is stored in aquifers through ground-water recharge or is stored on the land surface in lakes, marshes, and reservoirs. Runoff represents water from precipitation that runs directly off the land surface to streams and water discharged to streams that was stored in lakes, marshes, reservoirs, or aquifers.

Iowa, Michigan, Minnesota, Wisconsin↗

Reflections on writing hydrologic reports

Reporting of scientific work should be characterized by a logical argument that is developed through presentation of the problem, tabulation and display of data pertinent to the problem , and testing and interpretation of the data to prove hypotheses that address the problem. Organization of the report is vital to developing this logical argument: it provides structure, continuity, logic, and emphasis to the presentation. Each part of the report serves a specific function and each is linked by a connecting logic, the logical argument of the report. Each scientific report normally has a title, table of contents, abstract, introduction, body (of the report), and summary and/or conclusions. Organization of sections within the body of the report is exactly parallel to overall organization; subjects presented in the section title are developed by logical subdivisions and pertinent discussion. The summary and/or conclusions section culminates the logical argument of the report by drawing together and quantitatively reiterating the principal conclusions developed in the discussion. Supplemental information on report content, background of the study, additional data or details on procedures, and other information of interest to the reader is presented in the foreward or preface, list of illustrations or tables, glossaries, and appendixes. (Lantz-PTT)

Open-File Report↗

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↗

Water resources of Wisconsin, Fox-Wolf River basin

PURPOSE AND SCOPE The purposes of this report are to (1) describe the geohydrology of the basin, (2) describe and relate the surface- and ground-water systems, (3) discuss existing and possible future water problems in the basin, and (4) to suggest means of possible solutions. The scope of the study was to interpret and relate streamflow, climatic, geologic, and ground-water information. Because of its reconnaissance nature, this report should serve as background information. More specific water information for many areas of the Fox-Wolf River basin is available at the offices of the U.S. Geological Survey and the University of Wisconsin Geological and Natural History Survey in Madison. This study is part of a planned investigation of the geology and water resources of the rapidly developing Fox River valley industrial complex and municipal region extending from Green Bay to Fond du Lac. The related studies in this region cover Fond du Lac County (Newport, 1962), Outagamie County (LeRoux, 1957), Brown County (Drescher, 1953), the Green Bay area (Knowles and others, 1964; Knowles, 1964), Waupaca County (Berkstresser, 1964), Waushara County (Summers, 1965), and Winnebago County (Olcott, 1966).

Wisconsin↗