Water Resources Engineering Commons^™

The Influence Of Rainfall And Land Cover Change On Streamflow Variability In Eastern Florida Watersheds, Brynn Romberger

Theses and Dissertations

Streamflow in Florida watersheds is influenced by both land cover change and rainfall variability, but separating their contributions is difficult because both have changed over recent decades. This study evaluated rainfall trends and land cover change to determine which better explains flood and drought threshold exceedance across 27 USGS streamflow gauges within the St. Johns River Water Management District (SJRWMD) from 1985 to 2025. Streamflow was characterized using change-point, trend, and variability analyses with a six-threshold exceedance framework. Land cover was quantified using the National Land Cover Database (NLCD), rainfall characteristics were derived from the Analysis of Records for Calibration …

Evaluation Of Dredged Sediments As A Partial Replacement For Fine Aggregate In Mortar And Concrete, Ashish Gautam

Graduate Theses and Dissertations (2019 - present)

The feasibility of using dredged sediment from the Mobile River as a partial replacement for fine aggregate in mortar and concrete was investigated through a series of laboratory characterization and performance evaluation. Three dredged sediment samples (A, B and C) were initially examined, and Sample A was selected for further evaluation due to its closer resemblance to natural fine aggregate. This sample exhibited lower moisture content, higher sand equivalent values, higher specific gravity, and lower absorption. Mortar mixtures with 0, 10, 20, 30, 50, 75 and 100% dredged sediment replacement showed decreasing workability as the replacement level increased. The 20% …

Optimization Of The Baffle Geometry Of A Circular Culvert Outlet Structure To Maximize Energy Dissipation, Kiarash Shirmahi

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

High-velocity flow at culvert outlets can lead to significant soil erosion and damage to downstream infrastructure, particularly in agricultural regions where land protection is critical. Circular culverts, commonly used in transportation systems, are especially susceptible to this issue due to flow acceleration caused by geometric constraints and installation angles. Despite extensive research on energy dissipation in rectangular culverts, limited attention has been given to circular configurations. This study addresses this gap by evaluating the hydraulic performance of baffle systems designed to reduce outlet energy in circular culverts.

A series of laboratory experiments was conducted using a scaled physical model of …

Movable Bed Physical Model Investigation Of Bed Level Changes Caused By River Sediment Diversions, Hayden Cole Franklin

LSU Master's Theses

Since 1932, due to human and natural processes, over 2,000 square miles of Louisiana’s coast have been lost. River sediment diversions have been proposed as sustainable options to combat land loss. These projects, like the proposed Mid-Barataria Sediment Diversion, are designed to deliver sediment-rich Mississippi River water into nearby bays and estuaries, helping build and maintain land. However, river sediment diversions may alter river hydraulics and sediment transport, potentially inducing upstream degradation and downstream aggradation. Using the Lower Mississippi River Physical Model (LMRPM), this study quantitatively analyzed bed level changes as well as hydraulic conditions associated with the proposed Mid-Barataria …

Roadway Runoff Impacts To Trout Streams Studies For Ms4 Permit, Jobayed Hossain Badhan

College of Graduate Studies: Theses & Dissertations

Roadway runoff from Georgia Department of Transportation (GDOT) highway infrastructure poses measurable, but temporally constrained threats to cold-water trout ecosystems in northern Georgia. This study investigates temperature and dissolved oxygen (DO) dynamics in three secondary trout streams receiving GDOT roadway discharges, with the primary objective of evaluating compliance with Georgia Rule 391-3-6-.03(6)(ii),(v) under the Municipal Separate Storm Sewer System (MS4) permit framework. Field monitoring was conducted from April 2024 through October 2025 across two consecutive summer seasons using a tiered, multi-instrument approach: YSI ProDSS handheld grab sampling provided regulatory-grade reference measurements; HOBO MX-801 optical DO dataloggers recorded continuous 5-minute-interval temperature …

Flood Damage And Social Vulnerability In Coastal New Hampshire, Mitchell S. Berry

Honors Theses and Capstones

This study investigates the relationship between flood-induced building damage and social vulnerability in coastal New Hampshire, with a focus on communities increasingly affected by sea-level rise, storm surge, and high tide events. Using a dataset of 2,528 single-family homes, the analysis integrates flood depth maps (coastal, pluvial, and fluvial), building-level damage estimates, and a housing-burden-based metric to assess how physical and social factors interact to shape flood impacts. Results show that flood depth is the primary driver of building damage, with the most severe impacts concentrated in coastal areas experiencing deeper inundation. However, when buildings are grouped by vulnerability, higher …

Assessing Dissolved Organic Matter Sources And Dynamics In Urban Stormwater: Implications For Greenhouse Gases, Harper W. Schmalz

Theses and Dissertations (Comprehensive)

Stormwater management ponds (SWMPs) are important aspects of land-use planning and increasingly recognized as active sites of biogeochemical processing that influence carbon cycling; however, little research has investigated the controls on dissolved organic and dissolved inorganic carbon (DOC and DIC) within these systems. This thesis examined the processing and transformations of dissolved carbon between three compartments to support the development of a greenhouse gas (GHG) box-model for urban stormwater ponds, including SWMP sediment, surface water, and vegetation. The objective of this thesis was to assess the biogeochemical processes that govern the rate and transformation of DOC and DIC between these …

Sustainable Nutrient Management Opportunities For Small Communities In The U.S. With Lagoon Wastewater Treatment Systems, Denis Sigei Ruto

Graduate Theses, Dissertations, and Problem Reports (ETD)

Lagoon wastewater treatment systems are among the most widely used secondary treatment technologies serving small and rural communities in the United States due to their low capital and operating costs, minimal energy requirements, and operational simplicity. While effective for removal of organic matter and suspended solids, most lagoon systems were not designed to achieve advanced nutrient removal. As regulatory priorities increasingly emphasize control of total nitrogen and total phosphorus to protect receiving waters and public health, lagoon-dependent communities face growing compliance challenges. These challenges are exacerbated by aging infrastructure, limited technical capacity, financial constraints, and insufficient infrastructure data, highlighting the …

Occurrence Of Per And Polyfluoroalkyl Substances In Rural Wastewater Treatment Plants And Comparison To Large Treatments Plants, Madeleine Rauhauser

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Per and polyfluoroalkyl substances (PFAS) are a class of compounds defined by their carbon – fluorine bonds, which are incredibly strong. The strength of this bond makes these compounds very useful industrially, they are used as waterproof and grease proof coatings, and as fire retardants. The same thing that makes them useful industrially makes them incredibly recalcitrant in the environment, it is difficult to destroy these compounds. PFAS are also suspected to cause health impacts in people, such as kidney cancer and low birth weights. Wastewater has been commonly identified as a contributor to the amount of PFAS in the …