Environmental Engineering Commons^™

Predictive Modeling Of Riverine Constituent Concentrations And Loads Using Historic And Imposed Hydrologic Conditions, Mark Hagemann

Doctoral Dissertations

This research was principally concerned with the task of quantifying dissolved and suspended constituents carried in river water when direct measurements are not available. This is a question of scientific and societal relevance, and one with a long history of study and a great deal of remaining difficulty. The traditional approach to estimating these quantities, linear regression models (LMs), suffers from poor flexibility and high subsequent bias in many applications. This research applied semiparametric generalized additive models (GAMs), a more flexible class of regression models, evaluated their performance in various locations and conditions, and applied them in a proactive modeling …

Proactive Assessment Of Climate Change And Contaminant Spill Impacts On Source Water Quality, Lillian C. Jeznach

Doctoral Dissertations

Managing the water quality of surface drinking water sources has become an increasingly difficult task for water suppliers due to increased watershed urbanization and climate change. Changes in source water quality may affect public perceptions, treatment effectiveness, and ultimately costs to treat water to drinking standards. Although there are increased threats to current and future drinking water quality, current approaches to managing these threats are typically reactionary. Prior detailed modeling efforts of hypothetical events that may impair raw water quality allow for an understanding of constituent fate and transport, including potential maximum concentrations and travel times to the drinking water …

Water Quality Modelling Using Multivariate Statistical Analysis And Remote Sensing In South Florida, Mohammad Hajigholizadeh

FIU Electronic Theses and Dissertations

The overall objective of this dissertation research is to understand the spatiotemporal dynamics of water quality parameters in different water bodies of South Florida. Two major approaches (multivariate statistical techniques and remote sensing) were used in this study. Multivariate statistical techniques include cluster analysis (CA), principal component analysis (PCA), factor analysis (FA), discriminant analysis (DA), absolute principal component score-multiple linear regression (APCS-MLR) and PMF receptor modeling techniques were used to assess the water quality and identify and quantify the potential pollution sources affecting the water quality of three major rivers of South Florida. For this purpose, a 15-year (2000–2014) data …

Longitudinal Tidal Dispersion Coefficient Estimation And Total Suspended Solids Transport Characterization In The James River, Beatriz Eugenia Patino

Civil & Environmental Engineering Theses & Dissertations

The longitudinal dispersion coefficient is a parameter used to evaluate the effect of cross-sectional variations on substance mixing mechanisms in estuaries influenced by tide, wind and internal density variations. Considering a two dimensional approach, this study aims at evaluating a tidal area of the lower James River at approximately 19 miles upstream from the mouth at the Chesapeake Bay, in the City of Newport News, and applies an experimental procedure based on in-situ salinity concentrations to estimate the dispersion coefficient in the area where receives a discharge from the HRSD James River Wastewater Treatment Plant, and further characterizes Total Suspended …

Wetlands And Coastal Systems: Protecting And Restoring Valuable Ecosystems, C. T. Agouridis, K. R. Douglas-Mankin, A. C. Linhoss, A. R. Mittelstet

Biological Systems Engineering: Papers and Publications

Wetlands and coastal systems are unique, highly productive, and often threatened landscapes that provide a host of services to both humans and the environment. This article introduces a five-article Wetlands and Coastal Systems Special Collection that evolved from a featured session at the 2015 ASABE Annual International Meeting in New Orleans, Louisiana. The Collection provides perspectives on tools and techniques for enhancing the protection and restoration of wetlands and coastal systems with emphasis on vegetation, hydrology, water quality, and planning. Topics span the Florida Everglades (two articles) and Virginia floodplain (one article) wetland systems and include remote sensing (one article) …

Influence Of Stormwater Control Measures On Watershed Hydrology And Biogeochemical Cycling, Colin D. Bell

Open Access Dissertations

Urban development replaces vegetation with impervious surfaces and natural drainage channels with pipe networks that quicken flow paths and alter hydrologic regimes. Additionally, the import of food, application of fertilizer to lawns and gardens, and heightened atmospheric deposition increases nutrient availability in urban landscapes. These excess nutrients are ultimately routed to streams through the pipe networks before it can be processed by the vegetation and microorganisms of the landscape. This combination of physical and chemical disturbances impacts stream ecosystems and degrades their ability to perform valuable services such as removal of nutrients, degradation of pollutants, and provision of recreational and …

Long-Term Effects Of Forestry Best Management Practices On Hydrology And Water Chemistry In Three Appalchian Headwater Catchments, Kameryn I. Wright

Theses and Dissertations--Biosystems and Agricultural Engineering

In 1982, a study was initiated in the Field Branch watershed, in the University of Kentucky’s Robinson Forest, to evaluate forestry best management practice (BMP) effectiveness after intensive harvesting. The study utilized a paired watershed approach on three adjacent Field Branch subcatchments. One subcatchment was left as the control, one had BMPs implemented (including a 50-ft undisturbed buffer along the stream), and one was clear-cut to the stream’s banks without the use of BMPs (i.e. logger’s choice). Prior research has shown that logging can negatively impact watershed functions by altering stream hydrology, geomorphology, water quality, and instream habitat. Thus, the …

Water Quality Evaluation Of Tire Derived Aggregate, Richela K. Maeda

Projects

The primary objective of this study is to investigate the rate that potential water quality contaminants leach from tire-derived aggregate (TDA) as a function of time. A laboratory and field experiment is conducted to provide insight into both controlled and field settings. The laboratory portion of this study also provides a basis for evaluating the effect that alternating periods of wet and dry weather have on the potential water quality impacts of the leachate as compared to the worst-case operating condition, when TDA is constantly submerged (i.e., when placed below the permanent groundwater table). The field experiment is used to …

Evaluation Of Point Of Use Reverse Osmosis Systems For Drinking Water In Colonias, Oscar Daniel Ramirez

Open Access Theses & Dissertations

Clean drinking water is often considered a right and not a privilege, especially in first world countries. However, thousands of residents of colonias (settlements in the U.S. that lack access to basic infrastructure) struggle to obtain clean drinking water, including some in the Paso del Norte Region. Residents of colonias located in Doña Ana County, NM, and El Paso County, TX typically rely on domestic wells and hauled water, respectively, but these sources may be of inadequate quality, potentially posing a health risk due to microbiological contamination, presence of arsenic, or elevated concentration of total dissolved solids. This project brings …

Assessing Downstream Stormwater Impacts For Urban Watershed Planning, Johanna Meyer Pavlowsky

Masters Theses

"The urbanization of watersheds has caused debilitating effects to downstream aquatic ecosystems in catchments and streams. The implementation of green infrastructure (GI), such as permeable pavements and bioretention facilities, has been shown to alleviate these effects by both reducing runoff and mitigating pollutants; however, the implements are often not designed with a specific goal of water improvement. This study targets understanding a small, impaired urban watershed, and the benefits green infrastructure may have to provide environmental, social, and economic improvement to the watershed.

Portions of Rolla including much of the S&T campus drain into the impaired urban waterbody Frisco Lake, …

Removal Of Cattle Manure Constituents In Runoff From No-Till Cropland As Affected By Setback Distance, John E. Gilley, Aaron J. Sindelar, Brian L. Woodbury

Biological Systems Engineering: Papers and Publications

Vegetative filter strips located at the bottom of a hillslope have been shown to substantially reduce nutrients and sediment in runoff. Cropland areas could serve a similar function. However, little scientifically derived information is available to help identify the setback distances required to effectively reduce the transport of contaminants in runoff. The objective of this study was to determine the effects of setback distance and runoff rate on the concentrations and mass transport rates of selected constituents following land application of beef cattle manure to a no-till cropland area. The study site had a residue cover of 8.84 Mg ha-1 …

Removal Of Cattle Manure Constituents In Runoff From No-Till Cropland As Affected By Setback Distance, John E. Gilley, Aaron J. Sindelar, Bryan L. Woodbury

Biological Systems Engineering: Papers and Publications

Vegetative filter strips located at the bottom of a hillslope have been shown to substantially reduce nutrients and sediment in runoff. Cropland areas could serve a similar function. However, little scientifically derived information is available to help identify the setback distances required to effectively reduce the transport of contaminants in runoff. The objective of this study was to determine the effects of setback distance and runoff rate on the concentrations and mass transport rates of selected constituents following land application of beef cattle manure to a no-till cropland area. The study site had a residue cover of 8.84 Mg ha …