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Full-Text Articles in Hydraulic Engineering
Asbestos Cement Pipe Condition Assessment And Remaining Service Life Prediction, Abiy Melles Ghirmay
Asbestos Cement Pipe Condition Assessment And Remaining Service Life Prediction, Abiy Melles Ghirmay
Graduate Theses and Dissertations
This research details a condition assessment of asbestos cement (AC) pipe within in the Bella Vista Village Property Owners Association water distribution system. Bella Vista Village contains appropriately 300 miles of AC pipe with nominal diameters from 6-14 inch. The goal of the research is to determine the current condition of AC pipe within the system and predict future performance of the pipes. AC pipe samples were obtained from 23 locations disturbed across the distribution system with nominal pipe diameters of 6-8 inch. Estimates of current level of degradation were obtained using phenolphthalein staining and hardness measurements of each sample. …
Trend Analysis Of Water Quality In Northwest Arkansas Streams Reflects Changes In The Watershed, Zachary Paul Simpson
Trend Analysis Of Water Quality In Northwest Arkansas Streams Reflects Changes In The Watershed, Zachary Paul Simpson
Graduate Theses and Dissertations
Watershed export of nutrients, sediments, and chemicals impacts receiving waters. Changes within the watershed (e.g., anthropogenic or climatic) can alter the transport of constituents in streams. Stream monitoring is crucial for understanding these effects. This study developed a potential improvement to flow-adjusting constituent concentrations in streams, an important step of analyzing monitoring data in lotic systems for trends. The method incorporates a K-fold cross-validation procedure to optimize a model explaining the relationship between the concentration and streamflow, thus providing a valuable tool to researchers in water quality. Additionally, two case studies were conducted on watersheds located in northwest Arkansas using …
Evaluating A Measure-Calculate Method For Determining Sediment Oxygen Demand In Lakes, Adrian Beirise
Evaluating A Measure-Calculate Method For Determining Sediment Oxygen Demand In Lakes, Adrian Beirise
Graduate Theses and Dissertations
A steady-state mass diffusion model used with simple measurable and calculable inputs for determining sediment oxygen demand (SOD) is compared to an intact core incubation (ICI) SOD method using samples from three lakes. The mass diffusion model coupled with inputs is known as the measure-calculate method (M-C) and is a potential alternative to existing methods for measuring SOD which are more complex, time-consuming, and costly. The M-C method requires inputs for volumetric sediment oxygen uptake (Ṅsed), sediment density and porosity, and water properties. Ṅsed was determined by suspending sediment in oxygen-saturated water with a DO probe and determining the steady …
An Empirical Water Quality And Best Management Practice Prioritization Model For Select Arkansas Watersheds, James Mccarty
An Empirical Water Quality And Best Management Practice Prioritization Model For Select Arkansas Watersheds, James Mccarty
Graduate Theses and Dissertations
The purpose of this study was to prioritize subwatersheds using water quality data and watershed characteristics. Water quality data was provided through studies by the Arkansas Natural Resources Commission, Beaver Water District, Arkansas Water Resources Center, and publicly available USGS gage data. A total of 114 sites across five HUC-8 watersheds were analyzed, including 12 USGS gages. Watershed characteristic data was retrieved from USGS and Arkansas GeoStore geodatabase repositories. A significant linear relationship between baseflow and stormflow nutrient concentrations was established allowing for the use of baseflow concentrations in the prioritization methodology. Pearson correlation, linear regression, classification and regression tree, …
Magnitude And Frequency Of Floods For Rural, Unregulated Streams Of Tennessee By L-Moments Method, Hongxiang Yan
Magnitude And Frequency Of Floods For Rural, Unregulated Streams Of Tennessee By L-Moments Method, Hongxiang Yan
Graduate Theses and Dissertations
This study presents a regional frequency analysis of Tennessee using the well-known Bulletin-17B method standardly used in the United States and the relatively new and developing L-Moments methods. Flood frequency characteristics were defined for 416 gaging stations located primarily in rural and lightly developed areas of Tennessee. All the gaging stations have 10 or more years of record through 2006. Using the L-Moments method, the generalized extreme value distribution was identified as the most robust distribution for each of four hydrologic areas. Multiple regression equations were also calculated for estimating the flood frequency of ungaged, unregulated, rural streams in each …
Mathematical Modeling Of Fluid Spills In Hydraulically Fractured Well Sites, Oluwafemi Michael Taiwo
Mathematical Modeling Of Fluid Spills In Hydraulically Fractured Well Sites, Oluwafemi Michael Taiwo
Graduate Theses and Dissertations
Improved drilling technology and favorable energy prices have contributed to the rapid pace at which the exploitation of unconventional natural gas is taking place across the United States. As a natural gas well is being drilled, reserve pits are constructed to hold the drilling fluids and other materials returned from the drilling process. These reserve pits can fail, and when they do, plant and animal life of the surrounding area may be adversely affected. This project develops a screening tool for a suitable location for a reserve pit. This work will be a critical piece of the Infrastructure Placement Analysis …