Engineering Commons^™

Terrestrial Laser Scanning Technology For Measuring Streambank Retreat Along East Fork Poplar Creek And Calculating The Effect On Mercury Release., José L. Martínez Collado

Masters Theses

Mercury (Hg) is a globally distributed inorganic pollutants of human concern. The high toxicity is mainly related to the capacity of Hg species to accumulate and biomagnify along aquatic food webs. Along East Fork Poplar Creek (EFPC), erosion represents the principal mercury input into the local waters, eventually reaching humans through the food chain. This research project aimed to monitor streambank erosion along a mercury-contaminated creek using Light Detention and Ranging (Lidar) technology and erosion pins. A Terrestrial Laser Scanner (TLS) was used to generate high-resolution point clouds from August 2020 to January 2021 across nine streambank locations to detect …

Guía Metodológica Para La Recuperación De Suelos Afectados Por Erosión Hídrica Mediante El Uso De Terrazas, Evelyn Fernanda Contreras Contento, Diego Andrés Torres Ardila

Ingeniería Ambiental y Sanitaria

La erosión hídrica es un fenómeno natural que afecta los suelos con alta pendiente que generan degradación y a su vez pérdidas exorbitantes naturales, materiales como económicas, a pesar de darse naturalmente es un fenómeno que se puede mitigar y recuperar los daños generados por medio de técnicas específicas. Colombia tiene una alta tasa de erosión de suelos, causadas tanto por actividades antrópicas como naturales, se estima que cerca al 40% de los suelos del país se encuentran en algún estado de degradación por esta condición (SIAC, 2014). La “Guía metodológica para la recuperación de suelos afectados por erosión hídrica …

Susceptibility Assessment Of Bank And Floodplain Erosion In Stream Restoration Using A Two-Dimensional Hydrodynamic., Fereshteh Noorbakhsh

Electronic Theses and Dissertations

In the design of stream restorations, boundary shear stress (shear stress) and velocity during high flow events are the key parameters in the assessment of the risk of morphological failure associated with channel bank and bed erosion and sediment transport. The use of two-dimensional hydrodynamic models (2D Models) is becoming more common to estimate critical shear stress and velocity for stream restoration projects. These models can give detailed distribution of shear stress and velocity over floodplain surfaces and channel. Obtaining reliable and correct estimates of stress and velocity require an accurate digital terrain model, estimates of input flows at the …

Technology For Integrated Groyne-Vetiver Erosion Reduction (Tiger): Case Study In A West African River, Chase M. West

Dissertations, Master's Theses and Master's Reports

River erosion is a problem all over the world. The effects of river erosion are especially hard for farmers in developing countries, where the river is an important part of their farming practices and daily lives. A case study was done in the small village of Fode Binea in Senegal, West Africa to reduce this stream erosion. A new hybrid approach, Technology for Integrated Groyne-Vetiver Erosion Reduction (TIGER) method, was developed. The method includes combining groynes at the toe of the riverbank to reduce toe erosion in the channel and planting a buffer strip with vetiver grass to reduce erosion …

1-Dimensional Hydraulic And Sediment Transport Modelling Of An Emergency Spillway, Ryan Weise

Electronic Thesis and Dissertation Repository

Hydropower dams are complex structures that require a high level of safety. Systems approach and system simulation have provided new insights into evaluating dam safety. System simulation of hydropower dams requires that the physical state of the critical infrastructure be represented. A 1-dimensional hydraulic and sediment transport model was developed within HEC-RAS to address erosion in an emergency spillway for an existing system simulation model. Various inflow events were simulated, and the ensuing erosion was evaluated. A range of Manning’s roughness coefficients were tested and the sensitivity was minimal. Erosion and deposition values were not accurate but offer an understanding …

Sediment Transport Modelling Using Dynamic (Dis)Connectivity Prediction For A Bedrock Controlled Catchment, David Tyler Mahoney

Theses and Dissertations--Civil Engineering

The (dis)connectivity of sediment, defined as the detachment and transport of sediment from source to sink between geomorphic zones, is a major control on sediment transport rates but has seldom taken precedence in sediment transport models that focus on assessment of sediment impacts on water supply. A watershed-scale sediment transport model was formulated that incorporates sediment (dis)connectivity knowledge and subroutines and predicts sediment flux through coupling with an excessive shear stress erosion equation. The intersecting probabilities of sediment supply, detachment, transport, and (dis)connectivity produce the probability of sediment connectivity for a watershed or region of a watershed. The integration of …

Spatial And Temporal Analysis Of Land Cover Change, Sedimentation And Water Quality In The Lake Issaqueena Watershed, South Carolina, Cassie Pilgrim

All Theses

Soil erosion and increased sediment yields within a watershed lead to impaired water quality, decreased availability of wildlife habitat and reduced recreational opportunities. While some sedimentation occurs naturally within a water system, most erosion processes are the result of anthropogenic activities across a landscape, namely changes in land use and land cover (LULC). This study was conducted to determine temporal and spatial sedimentation trends in the Lake Issaquena watershed using sonar logging equipment, geographic information systems (GIS) and limited hydrologic data from the Soil Conservation Service (1941 and 1949). Sediment deposition was analyzed in relation to several key factors that …

A Spatial Analysis Of Streambank Heterogeneity And Its Contribution To Bank Stability, Paul Vanterpool Simmons

Masters Theses

Streambank erosion is a function of fluvial detachment and geotechnical failure mechanisms working in combination to cause bank retreat. It is generally agreed that bank stability is dependent on both types of erosion; however, few studies have attempted to correlate the driving and resisting forces between the two. It has been proposed that: (1) streambanks possess a spatial structure and dependence of non-erodible resistant structures such as root masses and rocks; (2) streambanks naturally “armor” themselves from fluvial erosion with a combination of hard points and resistive soil; and (3) the stability of the streambank can be predicted by the …

Evaluation Of Long Term Effects Of Erosion Due To Groin Placement In The Northern Yucatan Peninsula, Andrew V. Mahfood

Electronic Theses and Dissertations

This thesis documents the results of a study conducted to evaluate the long term effects of groin placement on beach re-nourishment and beach restoration in the Yucatan peninsula. The study includes the evaluation of six control points located on Chelem beach in Yucatan, Mexico, very close to the Progreso pier. The control points were set up in an active groin field to record data on the re-nourishment project covering the Chelem beach area. These erosion control groins were constructed as part of an experimental project to see how the adopted U.S. Army Corps of Engineers guidelines, for installing groins, affected …

Field And Numerical Investigation Of Wave Power And Shoreline Retreat In Terrebonne Bay, Southern Louisiana, Kyle Ryan Parker

LSU Master's Theses

The marshland in southern Louisiana is a vital resource that many people and wildlife depend on. Terrebonne Bay was chosen for this research because it has experienced one of the largest wetland loss rates among Louisiana estuaries. Investigations of wave power and shoreline retreat rate could provide decision makers with a better understanding of the contributing wave force responsible for local shoreline retreat. A strong relationship has been shown to exist between wave power and shoreline retreat [Schwimmer (2001) and Marani et al. (2011)]. Whether or not this strong relationship exists in Terrebonne Bay is the subject of this research. …

Stilling Basin Scour Remediation Using Air Injection And Flat Plate Extension, Rachael Barlock

Dissertations, Master's Theses and Master's Reports - Open

The South Florida Water Management District (SFWMD) is responsible for managing over 2500 miles of waterways and hundreds of water control structures. Many of these control structures are experiencing erosion, known as scour, of the sediment downstream of the structure. Laboratory experiments were conducted in order to investigate the effectiveness of two-dimensional air diffusers and plate extensions (without air injection) on a 1/30 scale model of one of SFWMD gated spillway structures, the S65E gated spillway. A literature review examining the results of similar studies was conducted. The experimental design for this research was based off of previous work done …

Shear Strength Evaluation Of An Erosional Soil System At Fourchon Beach, Jacques Pierre Boudreaux

LSU Master's Theses

South Louisiana is vanishing. Subsidence due to relative sea level rise with erosion of weak wetland soils together produce devastating rates of land loss for this area. It is believed that high rates of erosion are due to weak strength properties of fine-grained sediments in the beaches, marshes, and other wetlands in coastal Louisiana. Wave action is known to initiate the movement of weak coastal soils in a manner that is related to the difference between the shear stresses applied by waves and the critical shear strength of erosional sediments. Direct shear tests were performed on samples obtained from the …

Determining The Performance Of Breakwaters During High Energy Events: A Case Study Of The Holly Beach Breakwater System, Andrew Keane Woodroof

LSU Master's Theses

Breakwaters have been constructed in many areas along Louisiana’s coastline to protect the shoreline from wave energy and erosion. During normal conditions, these breakwaters can typically be analyzed using traditional empirical methods for emergent breakwaters. However, Louisiana’s coastline is under constant threat from tropical storms and hurricanes, during which breakwaters can frequently become overtopped or submerged systems. Recent studies show that the type of shoreline response to a breakwater system may vary depending on the crest height of the breakwater in relation to the mean water level. Though emergent breakwaters typically induce sediment accretion along the shoreline, studies using laboratory …

Particulate Organic Carbon Fate And Transport In A Lowland, Temperate Watershed, William Isaac Ford Iii

University of Kentucky Master's Theses

Small lowland agricultural systems promote conditions where benthic biological communities can thrive. These biogeochemical processes have significant impacts on terrestrial ecosystem processes including POC flux and fate, nutrient balances, water quality budges, and aquatic biological functioning. Limited information is available on coupled biological and hydrologic processes in fluvial systems. This study investigates the mixture of biological and hydrologic processes in the benthic layer in order to understand POC cycling in the South Elkhorn system. Further, comprehensive modeling of POC flux in lowland systems has not been performed previously and the behavior of potentially controlling variables, such as hydrologic forcing and …

Evaluation Of Unknown Foundations, Ronald W. Florkowski

USF Tampa Graduate Theses and Dissertations

In recent years, bridge foundations have been in the spotlight throughout the nation. Bridges built over running water are susceptible to erosion or scour around their foundations. The reduction in load capacity to piers and abutments pose a safety risk to highway motorists. It has become necessary for engineers to examine and monitor these "scour critical" bridges. The difficulty arises with subsurface foundations of which very little is known about their construction. Hence, the methods applied to analyzing "Unknown Foundations" have become a necessary topic of research.

This thesis explores a method to determine foundation lengths. Similar to Sonic Echo …