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Empirical Velocity Predictions at Culvert Inlets: Author: Patton, Jesse Earl; Date: 2006-05-15; Program: Civil Engineering; Abstract: The velocity distribution at the entrance cross section of a culvert is typically diverse, reflecting the nuances of the bed material, debris and other hydraulic factors just upstream of the culvert. These diverse inlet velocity fields have been observed to perpetuate some distance into the culvert, impacting the ability of fish to travel upstream in the culvert barrel. It is important to be able to quantitatively describe the inlet velocity field, especially as this serves as a necessary boundary condition for three-dimensional modeling of fluid flow in culverts. While there are various theor...; Download File | View full details

Advanced studies of fish passage through culverts: 1-D and 3-D hydraulic modeling of velocity, fish energy expenditure, and a new barrier assessment method: Author: Blank, Matthew David; Date: 2008-05-15; Program: Engineering; Abstract: Fish passage through culverts is an important component of road and stream crossing design. Although no comprehensive inventory of the number of culverts on fishbearing streams in the United States is available, there is an estimated 1.4 million streamroad crossings. The most common physical characteristics that create barriers to fish passage include excessive water velocity, insufficient water depth and large outlet drop heights. Over the past decade, interest in the effect culvert barriers have on aquatic systems has grown; accordingly, various passage assessment techniques have been used t...; Download File | View full details

A conceptual precipitation-runoff modeling suite: model selection, calibration and predictive uncertainty assessment: Author: Smith, Tyler Jon; Date: 2008-12-15; Program: Civil Engineering; Abstract: In Montana and much of the Rocky Mountain West, the single most important parameter in forecasting the controls on regional water resources is snowpack. Despite the heightened importance of snowpack, few studies have considered the representation of uncertainty in coupled snowmelt/hydrologic conceptual models. Uncertainty estimation provides a direct interpretation of the risk associated with predictive modeling results. Bayesian inference, through the application of Markov chain Monte Carlo methods, provides a statistical means of approximating uncertainty associated with both the parameters ...; Download File | View full details

Sensitivity of 1-D hydraulic models of fish passage in culverts to descriptions of fish swimming performance: Author: Nixon, Kyle Marshall; Date: 2009-08-15; Program: Civil Engineering; Abstract: One way culverts become barriers to the upstream movement of fish is by creating excessive velocities exceeding a fish's swimming ability. FishXing, a common tool for indirectly assessing fish passage, uses fish swimming ability information with one-dimensional culvert hydraulics to predict barrier status of culverts. However, since fish swimming ability data is scarce for many fish species, predictions of a culvert's barrier status can be inaccurate and overly conservative, possibly leading to misclassification or uneconomical design. Additional fish swimming ability research is necessary to ...; Download File | View full details