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C. A. Niehus

Publications and source records attributed to C. A. Niehus.

10 recordsLinked to original sources

Constructed impoundments in the floodplain: A source or sink for native prairie fishes, in particular the endangered Topeka shiner (Notropis topeka)?

Livestock watering holes (i.e., dugouts) are typically constructed in floodplains, yet the influence of dugouts on native prairie fishes is unknown. Such information is necessary for the effective management of native fishes, especially species of concern such as the endangered Topeka shiner (Notropis topeka). The goal of our study was to suggest technical guidelines for constructing floodplain wetlands that are compatible with stream fish resources. Specific objectives were to: determine the flood frequencies of the connection between streams and dugouts; determine fish community characteristics in floodplain dugouts; and, associate dugout characteristics with fish assemblages. A total of 20 dugouts within Six Mile Creek watershed, South Dakota, were surveyed seasonally (excluding winter) from fall of 2003 to fall of 2004. Dugouts were categorized according to their lateral floodplain placement (connectivity with the stream and flood frequency of the stream-dugout connection) and longitudinal placement across the watershed. Fishes were sampled in dugouts and adjacent stream reaches with seines and traps. The 21 species making up the stream and dugout fish assemblages were similar. Fish inhabited 65% of the dugouts; 30% contained Topeka shiners. Most fish inhabitance, and all Topeka shiner occurrences, were in dugouts that were headwater sites and were either directly connected to the stream or disconnected and frequently flooded (average 1 in 2 year event). Two dugouts in this latter category contained the most abundant, self-sustaining Topeka shiner populations. Constructing dugouts separate from the stream within frequently inundated zones can provide off-channel habitat for fishes.

Conference Paper↗

Characterization of stormwater runoff in Sioux Falls, South Dakota, 1995-96

The Kenai River in southcentral Alaska is an economically important salmon river generating as much as $78 million annually in direct benefits. Resource-management agencies are concerned that increased sedimentation and loss of streamside cover associated with accelerated erosion rates caused by boat activity may threaten salmon returns to the river. Bank loss and boat activity were characterized during 1996 along 67 miles of the Kenai River, including a segment of the river several miles long where boat activity is restricted to non-motorized uses. Bank loss in the non-motorized segment of the river was about 75 percent less than that observed in the highest boat-use area of the river and 33 per cent less than that observed in the lowest boat-use area of the river. Dates of peak boat activity coincided closely with chinook salmon returns to the Kenai River and with peaks in measured bank erosion. The boat activity period began in late May, peaked on weekend days in mid-July, and declined in early August. Observed boat traffic on the Kenai River included boats from 10 to 26 feet in length that transported 1 to 8 passengers. The most commonly observed boats were between 16 and 20 feet long and carried 4 or 5 passengers. The number of boats operated by commercial fishing guides represented 40 percent of the boats counted by the Alaska Department of Natural Resources, 55 percent of the boats counted by the Alaska Department of Fish and Game, and 57 percent of those recorded by observers during this study. The maximum boat activity and the maximum bank loss were measured at the RW's Campground study site about 16 river miles upstream from the mouth of the Kenai River. Between July 12 and September 10, 1996, more than 20,100 boats traveled by this site and the streambank along the inside of the meander bend was undercut to a depth of 45 inches at one measuring point. Boat activity and bank loss were greatest in areas of the river between about river miles 9 and 18 and river miles 39 and 46. These two segments of the river are popular residential and fishing areas and have banks composed of non-cohesive soils. In addition, a meandering, un-armored channel makes the banks along these two segments susceptible to erosion. The Kenai River in southcentral Alaska is an economically important salmon river generating as much as $78 million annually in direct benefits. Resource-management agencies are concerned that increased sedimentation and loss of streamside cover associated with accelerated erosion rates caused by boat activity may threaten salmon returns to the river. Bank loss and boat activity were characterized during 1996 along 67 miles of the Kenai River, including a segment of the river several miles long where boat activity is restricted to non-motorized uses. Bank loss in the non-motorized segment of the river was about 75 percent less than that observed in the highest boat-use area of the river and 33 percent less than that observed in the lowest boat-use area of the river. Dates of peak boat activity coincided closely with chinook salmon returns to the Kenai River and with peaks in measured bank erosion. The boat activity period began in late May, peaked on weekend days in mid-July, and declined in early August. Observed boat traffic on the Kenai River included boats from 10 to 26 feet in length that transported 1 to 8 passengers. The most commonly observed boats were between 16 and 20 feet long and carried 4 or 5 passengers. The number of boats operated by commercial fishing guides represented 40 percent of the boats counted by the Alaska Department of Natural Resources, 55 percent of the boats counted by the Alaska Department of Fish and Game, and 57 percent of those recorded by observers during this study. The maximum boat activity and the maximum bank loss were measured at the RW's Campground study site about 16 river miles upstream from the mouth of the Kenai River. Between July 12 and September 10, 1996, more than 20,10

Water-Resources Investigations Report↗

Scour assessments and sediment-transport simulation for selected bridge sites in South Dakota

Scour at bridges is a major concern in the design of new bridges and in the evaluation of structural stability of existing bridges. Equations for estimating pier, contraction, and abutment scour have been developed from numerous laboratory studies using sand-bed flumes, but little verification of these scour equations has been done for actual rivers with various bed conditions. This report describes the results of reconnaissance and detailed scour assessments and a sediment-transport simulation for selected bridge sites in South Dakota. Reconnaissance scour assessments were done during 1991 for 32 bridge sites. The reconnaissance assessments for each bridge site included compilation of general and structural data, field inspection to record and measure pertinent scour variables, and evaluation of scour susceptibility using various scour-index forms. Observed pier scour at the 32 sites ranged from 0 to 7 feet, observed contraction scour ranged from 0 to 4 feet, and observed abutment scour ranged from 0 to 10 feet. Thirteen bridge sites having high potential for scour were selected for detailed assessments, which were accomplished during 1992-95. These detailed assessments included prediction of scour depths for 2-, 100-, and 500-year flows using selected published scour equations; measurement of scour during high flows; comparison of measured and predicted scour; and identification of which scour equations best predict actual scour. The medians of predicted pier-scour depth at each of the 13 bridge sites (using 13 scour equations) ranged from 2.4 to 6.8 feet for the 2-year flows and ranged from 3.4 to 13.3 feet for the 500-year flows. The maximum pier scour measured during high flows ranged from 0 to 8.5 feet. Statistical comparison (Spearman rank correlation) of predicted pier-scour depths (using flow data col- lected during scour measurements) indicate that the Laursen, Shen (method b), Colorado State University, and Blench (method b) equations correlate closer with measured scour than do the other prediction equations. The predicted pier-scour depths using the Varzeliotis and Carstens equations have weak statistical rela- tions with measured scour depths. Medians of predicted pier-scour depth from the Shen (method a), Chitale, Bata, and Carstens equations are statistically equal to the median of measured pier-scour depths, based on the Wilcoxon signed-ranks test. The medians of contraction scour depth at each of the 13 bridge sites (using one equation) ranged from -0.1 foot for the 2- year flows to 23.2 feet for the 500-year flows. The maximum contraction scour measured during high flows ranged from 0 to 3.0 feet. The contraction- scour prediction equation substantially overestimated the scour depths in almost all comparisons with the measured scour depths. A significant reason for this discrepancy is due to the wide flood plain (as wide as 5,000 feet) at most of the bridge sites that were investigated. One possible way to reduce this effect for bridge design is to make a decision on what is the effective approach section and thereby limit the size of the bridge flow approach width. The medians of abutment-scour depth at each of the 13 bridge sites (using five equations) ranged from 8.2 to 16.5 feet for the 2-year flows and ranged from 5.7 to 41 feet for the 500-year flows. The maximum abutment scour measured during high flows ranged from 0 to 4.0 feet. The abutment-scour prediction equations also substantially overestimated the scour depths in almost all comparisons with the measured scour depths. The Liu and others (live bed) equation predicted abutment-scour depths substantially lower than the other four abutment-scour equations and closer to the actual measured scour depths. However, this equation at times predicted greater scour depths for 2-year flows than it did for 500-year flows, making its use highly questionable. Again, limiting the bridge flow approach width would produce more reasonable predicted abutment scour.

Water-Resources Investigations Report↗

Estimation of flood flows on the Big Sioux River between Akron, Iowa, and North Sioux City, South Dakota

This report presents estimated flood flows for specified frequencies at selected locations on the Big Sioux River between the Akron, Iowa, streamflow-gaging station and North Sioux City, South Dakota. The selected locations include: at the Akron gaging station, downstream from the Richland-Westfield Creek Basins, downstream from the Brule Creek Basin, downstream from the Upper West Boundary Big Ditch and Rock Creek Basins, downstream from Broken Kettle Basin, and downstream from North Sioux City. The flood flows for the 10-, 50-, 100-, and 500-year recurrence intervals will be used to support a Federal Emergency Management Agency Flood Insurance Study. Four methods were used to estimate the flood flows. The first method involved the use of drainage-area ratios raised to specified exponents to transfer the flood-frequency relation from the Akron gage to the selected downstream locations. The second method was a flood-frequency analysis based on a summation of the Akron gaging-station peak flows and concurrent tributary daily flows from within the various study reaches. The third method was an independence/dependence analysis of the Akron gaging-station flows and the tributary flows from the various study reaches. The fourth method was a flood-frequency analysis assuming complete dependence of the Akron peak flows and the tributary peak flows from the various study reaches. Based on the various analyses that were done, the drainage-area-ratio method best estimated the flood flows for the Akron to North Sioux City reach of the Big Sioux River. The best estimates of 10-, 50-, 100-, and 500-year flood flows at the location downstream from North Sioux City are 35,300, 70,400, 89,100, and 142,000 cubic feet per second, respectively.

Water-Resources Investigations Report↗

Water resources of Lincoln and Union counties, South Dakota

Water resources of Lincoln and Union Counties occur as surface water in streams and lakes and ground water in ten major glacial and one major bedrock aquifers. The major surface-water sources are the Missouri and Big Sioux Rivers. Glacial aquifers contain about 4 million acre-feet of water in storage; 1.5 million acre-feet are contained in the Missouri aquifer. The Wall Lake, Shindler, and Upper Vemillion-Missouri aquifers are deeply buried, confined aquifers with average thicknesses ranging from 31 to 41 feet. The Harrisburg and Big Sioux aquifers are shallow, water-table aquifers with average thicknesses of 26 and 28 feet, respectively. The Parker-Centerville, Newton Hills, and Brule Creek aquifers are buried, confined aquifers with average thicknesses ranging from 33 to 36 feet. The Lower Vermillion-Missouri aquifer is a buried, confined aquifer with an average thickness of 99 feet. The Missouri aquifer is confined in the northeastern portion of the aquifer and is a shallow, water-table aquifer elsewhere with average cumulative thickness of 84 feet.

Water-Resources Investigations Report↗