Engineering Commons^™

Slides: "Tightening Water Supplies”: Arizona And The Lower Basin States, Herb Guenther

Hard Times on the Colorado River: Drought, Growth and the Future of the Compact (Summer Conference, June 8-10)

Presenter: Herb Guenther, Arizona Department of Water Resources.

31 slides.

Hydrogeophysical Investigation At Luxor, Southern Egypt, Ahmed Ismail, Neil Lennart Anderson, J. David Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Over the past 35 years, the exposed stone foundations of the ancient Egyptian monuments at Luxor have deteriorated at an alarmingly accelerated rate. Accelerated deterioration is attributable to three principal factors: 1) excavation and exposure of foundation stone; 2) construction of the Aswan High Dam; and 3) changes in the regional groundwater regime. In an effort to better elucidate the hydrostratigraphy in the Luxor study area that extends from the River Nile to the boundaries of the Nile Valley and covers about 70 km², a geophysical/hydrological investigation was conducted. Forty Schlumberger vertical electrical soundings (VES), two approximately 6 …

Tide-Influenced Contaminant Transport In Coastal Aquifers, Yong Peng

Dissertations

Coastal aquifers are distinguished from other aquifers because of tidal effects which cause complicated groundwater flow and contaminant transport phenomena in regions immediately adjacent to the coast. This study is designed to address the significance of tidal influence on contaminant transport by focusing on one-dimensional homogeneous coastal aquifers.

This study formulates a conceptual model and corresponding flow and transport equations, analyzes coastal boundary conditions, solves numerically the transport equation, and uses experiments to verify the numerical results.

Results of numerical and experimental studies conclude that tides can have a significant impact on contaminant transport, especially when under unconfined conditions, subject …

Improvements In Groundwater Flow Modeling Through The Integration Of Resistivity Logs And Hydraulic Conductivity And The Use Of Variogram Uncertainty, Asheka Rahman

LSU Doctoral Dissertations

This study developed a coregionalized model to estimate hydraulic conductivity using spatial cross correlation between hydraulic conductivity and borehole geophysical data (a transform of the formation factor). An experimental pseudocross variogram is used instead of a cross variogram because data are not collocated. Experimental variogram uncertainty is investigated using confidence intervals for the experimental variogram calculated assuming variogram sills are lognormally distributed. These intervals are used for sensitivity modeling using kriging, cokriging, simulation and cosimulation. The hydraulic conductivity fields generated by kriging, cokriging, simulation, and cosimulation are then used in a high-resolution groundwater model created using telescopic mesh refinement (TMR) …

Tidal Forcing Groundwater Dynamics In A Restored Coastal Wetland: Implications Of Saline Intrusion, William Glamore, Buddhima Indraratna

Faculty of Engineering - Papers (Archive)

Tidal restoration projects are currently being undertaken throughout coastal Australia without a full understanding of the influence of tidal forcing on groundwater salinity. To determine the impact of restoring tidal flows on groundwater salinity levels, field investigations were undertaken at a study site near Berry, New South Wales. Fluctuations in groundwater and surface water chemistry (soluble chloride, pH, electrical conductivity) and hydrodynamics were measured over a 12 week period using multilevel piezometers and submersible data loggers spaced at discrete distances from a flood mitigation drain. Additional parameters, including saturated hydraulic conductivity (K_sat), were undertaken to determine baseline conditions …

A New Paradigm Of Modeling Watershed Water Quality, Fan Zhang

Electronic Theses and Dissertations

Accurate models to reliably predict sediment and chemical transport in watershed water systems enhance the ability of environmental scientists, engineers and decision makers to analyze the impact of contamination problems and to evaluate the efficacy of alternative remediation techniques and management strategies prior to incurring expense in the field. This dissertation presents the conceptual and mathematical development of a general numerical model simulating (1) sediment and reactive chemical transport in river/stream networks of watershed systems; (2) sediment and reactive chemical transport in overland shallow water of watershed systems; and (3) reactive chemical transport in three-dimensional subsurface systems. Through the decomposition …

Three Dimensional Modeling Of Wekiva Springshed With Wash123d, Sandeep Paladagu

Electronic Theses and Dissertations

This thesis presents a three-dimensional groundwater modeling of Wekia springshed in central Florida using a numerical model, WASH123D. Springs have historically played an important role in Florida's history. The Wekiva River is a spring-fed system associated with about 19 springs connected to the Floridan aquifer. With increased urbanization and population growth in this region, there has been an increased strain on the water levels of Floridan aquifer which is a major source of potable water. Maintaining groundwater recharge to the aquifer is a key factor of the viability of the regional water supply as well as Wekiva ecosystem. Hence, the …

Evidence Of Neotectonic Activity In Southwest Louisiana, Jordan Oliver Heltz

LSU Master's Theses

A methodology that combines high-resolution topographic mapping, field observations, subsurface evaluation, and geodetic data analysis has successfully located several fault-related geomorphic steps in an area of southwestern Louisiana once thought to be relatively devoid of such features. Comparison of height differences of benchmarks straddling these suspected fault-related steps shows that vertical displacement rates on faults in the study area ranged from about 2 mm/yr to as much as 6 mm/yr during the 1960’s and 1970’s. However, leveling data obtained as recently as January 2005 reveals that the majority of these faults are currently moving at rates of less than 1 …

Deep Drains To Manage Groundwater, Neil Cox, Sylvia Tetlow, Neil Coles

Bulletins 4000 -

A channel that is 1.0 m to 3.0 m in depth is considered to be a deep drain. The drain is excavated to a depth that is sufficient to intercept the watertable in order to capture and convey that groundwater from flat, poorly drained land.

The drain can either be ‘open’ to allow the inflow of surface water or ‘leeved’ to exclude surface water. An open deep drain has its spoil banks placed on one side or on alternate sides of the channel (Figure 1) while a leveed deep drain has continuous spoil banks placed on both sides of the …