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W.L. Broussard

Publications and source records attributed to W.L. Broussard.

At least 19 recordsLinked to original sources
USGS2012

Vegetation model technical report

The vegetation model (LAVegMod) described in this appendix is the next generation of a similar model (habitat switching module) initially developed as part of the Louisiana Coastal Area study. LAVegMod divides the original 5-habitat model for the Louisiana coast into 19 vegetation types. LAVegMod provides longer estimates of interannual variation in aboveground biomass; however, biomass varies with vegetation type. The model is intended as a tool for protection and restoration planning that provides repeatable estimates of the changes in species composition based on changes in hydrology and wetland area. This tool is dependent on other models that forecast changes in hydrology and wetland area.

Louisiana↗
USGS1979

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↗
USGS1978

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↗
USGS1976

Water resources of the Des Moines River Watershed, southwestern Minnesota

The Des Moines River drains about 1,350 square miles (3,496 km 2 ) of the north, west, and central parts of the watershed, and the East Fork Des Moines River along with several small creeks drain about 200 square miles (518 km 2 ) in the east part. These tributaries join the Des Moines river in Iowa. The watershed is on the Coteau des Prairies, the most prominent upland in southern Minnesota. the Coteau rises to altitudes of more than 1,900 feet (579 m) within the watershed. The west boundary is along the crest of the Coteau and was formed by a terminal moraine during late Wisconsin Glaciation. This moraine forms part of the divide between the Mississippi and Missouri Rivers. The north and east boundaries are also formed by morainic highs which represent recessions of the Des Moines lobe during late Wisconsin Glaciation. Surficial materials consist mostly of clayey drift with a few surficial outwash (sand and gravel) areas near the streams. Topographic quadrangle maps published by the U.S. Geological Survey are available for the entire watershed.

Minnesota↗
USGS1976

Water resources of the Rock River watershed, southwestern Minnesota

This Hydrologic Atlas is one of series describing the 39 watershed units in Minnesota. The 1,750 sq mi in the Rock River watershed are glaciated upland plain including all of Rock County and parts of Pipestone, Murray, Lincoln, Nobles and Jackson Counties. The average annual water budget shows 25.8 inches precipitation, 3.1 inches surface runoff and 22.7 inches evapotranspiration. Water use in million gallons for 1970 was 3 ,333 ground water and 274 surface water. Domestic supplies accounted for 37 percent livestock 37 percent, and industrial 26 percent of total use. All 18 municipalities use ground water, mostly from glacial drift, seven use water from Precambrian aquifers. Precipitation recharges ground water through glacial deposits. Water-table and potentiometric maps and section show ground-water movement. Highest streamflow results from snowmelt and spring rains followed by recession in flow through summer, fall, and winter. Surface water and ground water are both very hard. Surface water and water from surficial and shallow drift aquifers generally range from 450 to 1,000 mg/liter dissolved-solids concentrations. Water from deep drift and from bedrock generally exceeds 1,000 mg/liter dissolved-solids concentration except where Precambiian quartzite aquifers underlie pre-Wisconsin drift. (Woodard-USGS)

Minnesota↗
USGS1975

Water resources of the Zumbro River watershed, southeastern Minnesota

The Zumbro River drains 1,428 square miles and falls from about 1,300 feet altitude in its headwaters to 665 feet at its mouth. The remaining 248 square miles included in the watershed is drained by small creeks flowing directly into the Mississippi River. Distribution of water use is about as follows: domestic, 50 percent; farm (for irrigation and livestock), 18 percent; and industrial, 32 percent. Total usage, in water-budget terms, is 0.24 inch over the entire watershed, or less than 1 percent of inflow (average annual precipitation). Total quantity of water, thus, is of lesser concern than local availability and quality of water. The dominant ions (calcium, magnesium, and bicarbonate) and dissolved solids are reduced by dilution during periods of high water discharge in the Zumbro River at Zumbro Falls. Similarly, in the South Fork Zumbro River near Rochester, dominant ions, dissolved solids, and those ions that are increased by waste disposal (sodium, chloride, and nitrates) are all reduced by dilution at high water discharge. For the Zumbro River the smallest monthly range and the most uniform daily mean discharge usually occurs in January, whereas the greatest range usually occurs in March. The lowest flows usually occur in the winter and the highest during the spring ice breakup. The lowest observed flow, 47 cfs, occurred on February 18, 1961 and the highest, 23,600 cfs, occurred on March 29, 1962. Seventeen of 22 municipalities obtain at least part of their water supply from the Prairie du Chien-Jordan aquifer. Although only one town uses the Galena aquifer, a large number of private domestic wells are completed in it in the western part of the watershed. (Woodard-USGS)

Minnesota↗
USGS1975

Water resources of the Root River watershed, southeastern Minnesota

This Hydrologic Atlas is one of a series describing the 39 watersheds in Minnesota. The Root River watershed includes Houston, Winona, and parts of the surrounding counties. The 2 ,570 square miles in the watershed varies from gently rolling prairie in the west to an area of plateaus separated by valleys deeply incised into bedrock in the north and east. The average annual water budget for 30 years shows 29.5 inches of precipitation, 7.2 inches of surface runoff, and 22.3 inches of evapotranspiration. Water use in millions of gallons for 1970 was established at 7,310 of ground water and 6,700 of surface water. Domestic supplies accounted for less than one fourth and thermoelectric power for about one half of the total use. All 33 municipalities use ground water from bedrock aquifers, and 21 of those obtain at least part of their supply from the Prairie du Chien-Jordan aquifer. Many private domestic wells are completed in a shallow limestone aquifer. The ground-water system is recharged primarily by infiltrating precipitation in upland areas Ground-water movement is indicated by water-table and potentiometric maps and section diagrams. Water from bedrock and glacial aquifers generally is of acceptable quality for domestic use, dissolved solids generally less than 400 mg/liter very hard , and locally high iron content. The Mount Simon-Red clastics aquifer is locally saline. Runoff is greatest during the spring when snowmelt occurs and the soils are generally saturated.

Minnesota↗
USGS1975

Water resources of the Cedar River watershed, southeastern Minnesota

The Cedar River Watershed Unit (as established by the states of Minnesota) consists of 1,204 square miles (3,118 square kilometres) of flat or gently undulating plain. The watershed is drained by the Cedar River and several smaller streams that flow south into Iowa and eventually into the Mississippi River. Its easternmost neck is part of a broad, flat, well-drained plain, covered by a thin sheet of glacial drift. Sinkholes have formed in the near surface carbonate bedrock, and a karst topography is developing. Farther north, along the east boundary, the drift is more than 200 feet (61 m) thick, and the land surface reaches altitudes of more than 1,450 feet (442 m) – the highest area in southeastern Minnesota. In the central part of the watershed in the southern flood plain of the Cedar River, the drift is less than 100 feet (30 m) thick, and the land surface altitude is less than 1,140 feet (347 m). The western part is dominated by a terminal moraine of the last Wisconsin glacier. Here the drift is more than 300 feet (91 m) thick, is poorly drained, and has numerous lakes. The watershed is mostly prairie and is well suited for farming, which is the dominant economic activity. Topographic quadrangle maps published by the U.S. Geological Survey are available for the entire watershed.

Minnesota↗
USGS1974

Water resources of the Snake River watershed, east-central Minnesota

Glacial drift overlies sedimentary, igneous, and metamorphic rocks in the Snake River watershed. The Snake River, which drains an area of about 1,030 square miles, originates in an extensive area of peat bogs in the northern part of the watershed. It flows southward across gently rolling glacial terrain in which the major relief is near the river. Near the southern boundary of the watershed, the Snake River turns eastward to its confluence with the St. Croix River. The northwest half of the watershed is heavily forested, whereas much of the southeast half has been cleared. The largest communities in the watershed, Mora and Pine City, had 1970 populations of 2,582 and 2,143, respectively.

Minnesota↗
USGS1974

Water resources of the lower St. Croix river watershed, east-central Minnesota

The lower St. Croix River watershed is an elongate area of about 930 square miles bounded on the east by the St. Croix River. The St. Croix River forms the Minnesota-Wisconsin boundary along the eastern side of the watershed. Additional drainage to the St. Croix River includes areas of about 2,500 square miles upstream in Minnesota and about 4,340 square miles in Wisconsin. At the southern tip of the watershed, the St. Croix joins the Mississippi River. Because part of the St. Croix River is deeply entrenched, topography in the watershed ranges from relatively rugged in highly dissected areas near the river to nearly flat in the west-central area. In the southern third of the watershed and along the St. Croix River, many outcrops of Ordovician, Cambrian, and Precambrian bedrock occur. The remainder of the watershed is covered by glacial deposits whose maximum thickness is about 400 feet. Much of the original forest cover, primarily hardwoods, has been removed; the largest concentrations remaining are long the St. Croix River and in the west-central area. The proximity of the watershed to the expanding Minneapolis-St. Paul metropolitan area emphasizes the importance of defining water resources essential for future growth.

Minnesota↗
USGS1974

Water resources of the Cannon River watershed, southeastern Minnesota

The 1,462 square miles of land surface in the Cannon River watershed varies considerably from areas of low hills and plains to areas dominated by streams deeply incised into bedrock. Much of the south-central part of the area consists of a till plain that ranges in altitude from 1,100 to 1,200 feet above mean sea level. This plain is bordered by end moraines that form ridges on the east, west, and south. The eastern moraine marks the maximum eastward extend of the Wisconsin glacier, rising to more than 1,300 feet above sea level and forming ridges 50 to 100 feet above the till plain. In the northwest, the end moraine ridges are less obvious but extend directly north across the Cannon River valley. The end moraine ridges were cut by glacial melt water, which also deepened the pre-existing Cannon River valley. This deeply incised valley captures some of the streams that flow westward off the end moraines. East of the end moraines, pre-Wisconsin age glacial deposits are relatively thin and deeply weathered and eroded. Lard glacial melt-water valleys, around Cannon Falls and extending several miles to the west and south west, are characterized by broad valley floors underlain by outwash sand and gravel. The Cannon River flows out of the watershed and enters the Mississippi River at about 660 feet altitude.

Minnesota↗
USGS1974

Water resources of the Blue Earth River watershed, south-central Minnesota

The Blue Earth River Watershed in Minnesota includes 3,106 square miles of land surface, which varies from fairly flat to gently rolling. The drainage extends south to include an additional 450 square miles in Iowa. The western, southern, and eastern boundaries are end moraines formed by Pleistocene glaciers. Major streams have eroded channels 40 to 75 feet deep in headwater regions and 150 to 200 feet deep near the mouth of the Blue Earth River at Mankato. In their lower reaches major streams have cut through glacial deposits and into underlying bedrock (described on ground-water sheet).

Minnesota↗
USGS1974

Water resources of the Lower Minnesota River Watershed, south-central Minnesota

The lower Minnesota River watershed, an area of 2,005 square miles, is fairly flat west of the Minnesota River, but rises to a hilly ridge along the east side of the watershed. Most of the area is covered by ground moraine cut deeply by the Minnesota River and less deeply by its tributaries. Surface drainage is toward the Minnesota River at the northeast corner of the watershed. The configuration of the water table, generally between 10 and 50 feet below land surface, is a subdued replica of the land surface. Shallow ground water moves generally toward local streams and then into the Minnesota River.

Minnesota↗