Water Resource Management Commons^™

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 …

Examining Extremes: A Comparison Between Machine Learning Based Southwestern Conus Seasonal Drought And High Fire Risk Event Synoptic Climatologies, Ethan M. Greenberg

School of Natural Resources: Dissertations, Theses, and Student Research

The Southwestern United States (SW CONUS), comprised of California, Arizona, Nevada, and Utah, is a vast region that tens of millions of people call home. Hosting ecosystems ranging from grasslands and shrublands to temperate forests and climate zones ranging from Mediterranean climates to arid deserts, the region is nearly unanimously prone to intense droughts and devastating wildfires. While fire weather conditions and drought are often studied separately or mentioned as background conditions for the other, there are relatively few studies that compare the typical meteorological conditions between the two. This study aims to more closely understand the meteorological relationship between …

Gaining Mussel: Evaluating Reintroduction Success Of Native Freshwater Mussels In Nebraska And Eastern Wyoming, Travis A. Moore

School of Natural Resources: Dissertations, Theses, and Student Research

Freshwater mussels are one of the most imperiled groups of organisms in North America, with over two-thirds of species considered threatened, endangered, or of special concern. These long-lived bivalves are essential to stream ecosystems, acting as filter feeders that improve water quality and as indicators of aquatic health. In Nebraska and Wyoming, native mussel populations have declined sharply due to habitat modification, pollution, and reduced connectivity. Two species of particular concern are the Plain Pocketbook Lampsilis cardium, listed as Tier I at-risk in Nebraska, and the Fatmucket Lampsilis siliquoidea, a Tier II at-risk species. In response, state agencies …

Passive Microwave Remote Sensing Of Flash Drought Impacts On Vegetation, Quinton R. Deppert

School of Natural Resources: Dissertations, Theses, and Student Research

In 2002, Dr. Mark Svoboda characterized a new form of drought known as flash drought. Flash drought was defined as a rapid decline in vegetation health caused by severe heat and drought. In recent years, attempts to quantify the impacts of flash drought via precipitation, soil moisture, evapotranspiration, and temperature indicators have proliferated. What has rarely been quantified is what the rapid decline in vegetation health amid flash drought looks like through remote sensing. This is because vegetation health indices like the Normalized Difference Vegetation Index (NDVI) are derived from the visible and infrared regions of the electromagnetic spectrum and …

Transport Phenomena Of Multiphase Flow And Slippery Microsphere Suspensions In Confined Space, Ryan Haggerty

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Understanding multiphase flow has many important environmental and engineering applications. For example, understanding gas flow in porous media is useful for energy storage, petroleum engineering, and contaminant cleanup. Nano- and microparticle transport is vital for enhanced oil recovery techniques and environmental contamination. Despite their relevance to environmental engineering, multiphase flows, especially with concentrated particle suspensions, are still a complex and developing topic. Additionally, hydrophobic surfaces are a relatively new area of research, for while the effects of hydrophobicity are observable, the mechanisms may occur on several scales. Hydrophobicity leads to a property called “slip,” which contradicts the traditional treatment of …

Water Current, Volume 58, No. 1, Spring 2026

Water Current Newsletter

No abstract provided.

Monitoring Terrestrial Ecosystem Productivity Using Hyperspectral Satellite Data, Serge Tuyambaze

School of Natural Resources: Dissertations, Theses, and Student Research

Accurate estimation of terrestrial Gross Primary Productivity (GPP) is critical for quantifying global carbon sequestration and understanding the terrestrial carbon cycle. While eddy covariance (EC) towers provide standard flux measurements, upscaling these measurements to continuous global coverage remains challenging due to the sparse distribution of flux towers and their small footprints. Remote sensing (RS), especially coupled with eddy covariance data, has been used to estimate GPP at the global scale. Different RS derived productivity models have been developed, including vegetation indices, light use efficiency (LUE) models, solar-induced fluorescence (SIF), dynamic global vegetation models (DGVM), and machine learning. One widely adapted …

Assessment Of Soybean Response To Irrigation Variability In Eastern Nebraska Using The Aquacrop Model, Anmol Singh, Saleh Taghvaeian, Yufeng Ge, Derek M. Heeren, Frank Bai

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Soybean [Glycine max (L.) Merr.] is a major irrigated crop in eastern Nebraska, where recent expansions in irrigated agriculture and projected trends in irrigation demand necessitate thorough investigations of approaches that can optimize its irrigation management. In this study, the AquaCrop model was calibrated and validated using 19 variable irrigation treatments from a five-year field experiment. The model accurately simulated canopy cover, soil water content, and grain yield, with validation normalized root mean square error (nRMSE) of 12%, 7%, and 7%, respectively. The model was subsequently applied to estimate soybean yield and water requirement during a 15-year period (2010–2024) …

Evaluating The Preparedness Of Local Zoning Regulations For Flood Risk Reduction In The Most Affected Local Jurisdictions In Nebraska, Md Asaduzzaman Noor

Community and Regional Planning Program: Theses

Flooding has profound social, economic, and environmental impacts on local communities, and zoning plays a critical role in mitigating these risks. The 2019 Nebraska floods, among the most severe in the state’s history, highlighted the urgent need to strengthen local preparedness and mitigation strategies. This study assesses the extent to which local zoning regulations in Nebraska’s most affected jurisdiction, including rural areas, address flood risk reduction. A systematic review of 117 zoning ordinances from counties, cities, towns, and villages, we applied a structured analytical framework encompassing regulatory and permitting policies, voluntary and incentive-based measures, and nature-based solutions. The results show …

Bridging Conservation And Disaster Recovery: A Dual Study On Wetland Program Plans Evaluation And Midwest Post Disaster Recovery Assessment, Rao Nargis Jahan

Community and Regional Planning Program: Theses

Wetlands provide essential ecological, social, and economic benefits for our society. In the United States, states and tribes play crucial roles in wetland protection, restoration, and management. However, no research has systematically measured state-level wetland planning efforts towards national conservation goals. This study is the first to comprehensively evaluate how state-level Wetland Program Plans (WPPs) align with national missions, particularly the "no-net-loss" of wetlands goal. Our research assesses the EPA-approved state-level WPPs from 42 out of 50 states in the United States during the period from 2015 to 2024. Using a protocol of 30 indicators across five categories, this study …

An Integrated Modeling Framework To Evaluate Circularity Of The Corn–Water–Ethanol–Beef Nexus, Heydi Han

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation examines the transition from conventional linear agricultural and food bioenergy systems toward more circular, resilient, and resource-efficient configurations. Prior research indicates that spatial and temporal variability in soil, weather, animal biological responses, and management decisions strongly influences productivity, nutrient-use efficiency, and profitability. Studies have also shown that a diversified circular system can buffer these sources of variability, improving stability and adaptive capacity. Building on these insights, the central focus of this work is to develop an integrated modeling framework to evaluate circularity within the Corn-Water-Ethanol-Beef (CWEB) nexus and explore how climate variability and management choices shape system-wide performance. …

Rainfall-Runoff Modelling In An Indonesian Humid Tropical Area Using Satellite-Based Precipitation Products, Noordiah Helda

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation explores three rainfall-runoff models in the humid tropical regions of Indonesia using satellite-based precipitation products (SBPPs) and develops integrated machine-learning modeling frameworks. Several ground-based observations from BMKG (Badan Meteorologi, Klimatologi, dan Geofisika (also known as the Indonesian Agency for Meteorology, Climatology, and Geophysics)) stations across Indonesia (133−165 stations) are compared and evaluated against satellite products, indicating that GPM performs well, with R-squared values ranging from 0.54 to 0.76 and correlation coefficients ranging from 0.45 to 0.69, respectively.

In the Martapura Watershed, South Kalimantan, due to a lack of observational discharge data, streamflow was generated using the FJ Mock …

Detecting Prescribed Fire, Haying And Grazing Events Via Remote Sensing To Create Grassland Disturbance Landcovers For The Ring-Necked Pheasant (Phasianus Colchicus), Megan A. Baldissara

School of Natural Resources: Dissertations, Theses, and Student Research

This dissertation developed disturbance detection models to fulfill the need for remote sensing landcover products describing grassland structure. The use of landcover products derived from remote sensing is increasing over time in pheasant (Phasianus colchicus) research. Such landcover, however, does not provide relevant pheasant structural habitat information (Chapter 1). Pheasants require tall, high-density grassland for nesting, tall grassland with medium density for brood rearing, and tall grassland for wintering. Time since disturbance can serve as a proxy for structure, as it shapes vegetation by removing biomass and resetting succession. Disturbance is easier to detect than structure with current …

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 …

Water Current, Volume 57, No. 3, Fall 2025

Water Current Newsletter

No abstract provided.

A Better Great Plains: Bridging The Implementation Gap For A Better Future, David W. Sandahl

School of Natural Resources: Dissertations, Theses, and Student Research

The Northern Great Plains is experiencing extensive native grassland loss and landscape degradation, jeopardizing both ecological integrity and the socio-economic systems that rely upon these ecosystems. In an early effort to lessen degradation, the United States Department of Agriculture (USDA) introduced the Conservation Reserve Program (CRP) which generated ecosystem services benefits such as reduced soil erosion, improved water quality, and increased species diversity through the retirement of cropland and rangeland for 10- or 15-year contracts. However, CRP has not fully modernized alongside today’s agriculturalists and adoption remains shaped by an historically fraught socio-political context characterized by deep-seated mistrust between ranchers, …

Understanding And Assessing Climate Change: Preparing For Nebraska’S Future, 2024 Climate Change Impact Assessment Report, Deborah J. Bathke, Eric Hunt, Heather Akin, Andrea D. Basche, Jesse E. Bell, Daniel R. Dileo, Ross Dixon, Martha Durr, Tonya Haigh, Francis John Hay, Kristina W. Kintziger, Nicholas A. Mcmillan, Hank Miller, Jerome Okojokwu-Idu, Crystal Powers, Tirthankar Roy, Zhenghong Tang, W. Ryan Wishart, Aaron R. Young, Sarah A. Sonsthagen, Jonathan J. Spurgeon

School of Natural Resources: Faculty Publications

Contents

Report Team

Acknowledgments

Executive Summary

Introduction

Climate Change Contexts: Global, National, and State

Observed Changes in Nebraska's Climate

Projections of Nebraska's Future Climate

Water Systems

Energy

Ecosystems

Agriculture

Human Health

Communities and the Built Environment

Indigenous Peoples

Climate Justice and Equity

The Response of Faith Communities

Nebraskans' Perceptions of Climate Change

Next Steps and Future Work

Supplemental Report: Adaptation, Risks, and Impacts

About the Authors

Faith-based Communities Survey

Evaluated Plans and Assessments

References

Evaluation Of Performance Characteristics And Groundwater Contamination Risks Associated With On-Farm Swine Carcass Disposal Via Composting And Shallow Burial With Carbon, Gustavo Castro Garcia

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation evaluates the performance of three on-farm swine carcass disposal methods: whole carcass composting (WCC), ground carcass composting (GCC), and shallow burial with carbon (SBC), focusing on biosecurity factors and groundwater contamination risks. Foreign animal diseases (FADs), such as African swine fever and classical swine fever, pose severe economic and animal well-being risks if introduced to the United States. With confirmation of an FAD, swine movement will be halted, creating an urgent need for practical, biosecure, and environmentally responsible on-farm disposal strategies for swine carcasses. Nebraska, as a leading swine-producing state, exemplifies the vulnerability of high-density livestock regions to …

Resilience Of Interdependent Transportation And Healthcare Systems: A Simulation-Driven Framework Incorporating Social Equity And Facility Optimization, S. Yasaman Ahmadi

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The overarching goal of this dissertation is to develop an integrated, simulation-driven framework to assess and enhance the resilience of interdependent transportation and healthcare systems before, during, and after natural hazards. By examining how spatial disruptions, social vulnerability, operational constraints, and infrastructure interdependencies affect access to and functionality of hospitals, this research offers a multifaceted evaluation of system performance under stress. This dissertation examines the impact of natural hazards, particularly floods, on the interdependent transportation and healthcare systems. The proposed approach combines and advances GIS-based network analysis, graph-theoretical modeling, and discrete-event simulation to evaluate system performance under different scenarios. The …

Multiscale Drivers Of Water Level Fluctuations And Nutrient Availability In Small Intermittent Reservoirs In The Us Midwest, Uchechukwu Vitus Chinatu Ogbenna

School of Natural Resources: Dissertations, Theses, and Student Research

Reservoir dynamics are often captured by fluctuations in water surface elevation, which reflect a complex interplay of hydrologic inputs, climatic conditions, land use influences, and management operations. While water level fluctuations (WLFs) in large regulated systems have been widely studied, the drivers and implications of WLFs in small reservoirs, particularly those fed by intermittent streams, remain poorly understood. Here, we examined the temporal dynamics of WLFs and their relationship with nutrient availability in nine small reservoirs in the U.S. Midwest using daily records from 1985 to 2022. We used water level classification from modified Zscore and transition matrices to assess …

Flooding: Risk Assessment And Its Interaction With Population & Environmental Health, Shivendra Srivastava

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Flood events have significant implications for both population and environmental health. This dissertation aims to explore flood risk and its interaction with humans and the environment. The key questions addressed in this dissertation include improving the existing flood risk framework to better assess population vulnerability and associated risk. Additionally, it explores how interactions among risk components vary across spatial scales and regions, and how these variations influence overall flood risk. The dissertation also investigates how to design a vulnerability component specific to flooding within flood risk estimation. Finally, it answers whether flood-specific vulnerability differs for a population compared to vulnerability …

Zambia's Poor Septic Waste Management: A Disaster In Waiting, Andrew Mwape

School of Natural Resources: Faculty Publications

In the shadows of Zambia’s rapidly growing urban and peri-urban communities lies an invisible but mounting threat, the mismanagement of septic waste. While national dialogue often focuses on economic development, climate change, or energy, the sanitation crisis receives little public attention, yet it poses an equally severe risk to public health, environmental integrity, and sustainable urbanization. Zambia’s poor septic waste management, if left unaddressed, is a disaster in waiting.

Septic waste refers to the wastewater and solid waste that flows from toilets, sinks, and other domestic plumbing fixtures into on-site sanitation systems such as septic tanks or pit latrines. This …

Groundwater Flooding On Highways In The Nebraska Sandhills: Applying Remote Sensing, Precipitation And Groundwater Modeling To Determine Depth, Cause And Frequency, Aaron R. Mittelstet

Nebraska Department of Transportation: Research Reports

Climate change significantly impacts infrastructure sustainability, particularly through shifts in precipitation patterns, intensity, and duration. These precipitation dynamics may increase the occurrence of surface water and groundwater flooding. Groundwater in the Nebraska Sand Hills (NSH), including the thickest portions of the High Plains Aquifer, extends close to the land surface in interdunal areas, making the NSH vulnerable to groundwater flooding. Recent events involving heavy precipitation, snow melt, and rising groundwater levels have caused prolonged highway flooding, disrupting transportation networks. This study estimates groundwater flood inundation depth, duration and frequency in the highways of NSH using remote sensing techniques and groundwater …

Adaptation Planning To Mitigate Flood Risk: Bellevue, Nebraska As A Case Study, Michael Nti Ababio

Community and Regional Planning Program: Theses

Flooding remains one of the most pressing natural hazards in the United States, with increasing frequency and intensity driven by climate change. This thesis explores the adaptation planning strategies employed to mitigate flood risks in Bellevue, Nebraska, a city significantly impacted by the 2019 floods in eastern Nebraska. Using a mixed-methods approach, the study combines quantitative analysis of flood vulnerability with a critical review of local planning policies using documents, zoning ordinances and institutional frameworks. Spatial analytical tools such as Global Moran’s I and Hot Spot Analysis (Getis-Ord Gi*) were used to detect clustering of inundated buildings during the 2019 …

Water Current, Volume 57, No. 2, Summer 2025

Water Current Newsletter

No abstract provided.

Response Of Soybean To Variable Irrigation Levels In Eastern Nebraska Using The Aquacrop Model, Anmol Singh

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

AquaCrop was calibrated and validated for soybean [Glycine max (L.) Merr.] using 19 irrigation treatments from five years using data from field experiments. The model accurately simulated canopy cover (CC), soil water content (SWC), and grain yield, with overall validation nRMSE values of 12%, 7%, and 7%, respectively. The overall validation nRMSE for SWC in individual 30-cm soil layers was comparatively higher, at 19%. The model was subsequently applied for long-term simulations (2010–2024) to estimate soybean yield and water requirements for two dominant soil types, Yutan silty clay loam and Tomek silt loam under three irrigation levels - rainfed, …

Assessing Spatial And Temporal Variation In Photoprotective Responses Of Deciduous And Evergreen Tree Canopies With Leaf Spectroscopy, Alexander Piper

School of Natural Resources: Dissertations, Theses, and Student Research

Environmental conditions frequently prevent carbon fixation by plants, leading to the absorption of excess light that can damage photosynthetic machinery if not dissipated. To do so, plants utilize several photoprotective mechanisms, some detectable remotely using Photochemical Reflectance Index (PRI). Two components of PRI correspond to the facultative engagement of the xanthophyll cycle (ΔPRI) and constitutive changes in xanthophyll pigment pool sizes (PRI0), representing distinct mechanisms regulating shorter and longer-term photoprotection, respectively. Our understanding of interspecific and intraspecific variation in these mechanisms is limited, primarily because PRI components are often not clearly distinguished. This study aimed to assess the variation in …

Assessment Of Sampling Gears For Bigheaded Carp In Mid-Order Prairie Rivers In Nebraska, Brett M. Anderson

School of Natural Resources: Dissertations, Theses, and Student Research

Silver Carp Hypophthalmichthys molitrix and Bighead Carp H. nobilis (collectively bigheaded carp) have invaded tributaries to the Missouri River and Platte River in Nebraska, USA. Information pertaining to efficient sampling protocols for assessing bigheaded carp populations as well as benefiting removal efforts is needed. Herding is a method used to increase the capture efficiency and detection probability of adult bigheaded carp by simultaneously using active and passive sampling gears. During June-July 2023, four herding techniques were assessed regarding their ability to elicit directional movement past an enclosure gate. The combination of sound and electrofishing resulted in the highest mean …

Drainage Area Limitations Of Single Watershed, Peak Flow Estimates From Nrcs Methods, Timothy A. Maughan, Rollin H. Hotchkiss, Riley Hales

Nebraska Department of Transportation: Research Reports

Most state Department of Transportation roadway design sections predict peak flow for culvert design using, amongst other approaches, Natural Resources Conservation Service (NRCS) TR-20 technology. Even though this technology is more than 50 years old, there are no clear guidelines for how large a single watershed drainage area may be while remaining appropriate for predicting peak discharge with this method. Our objective was to identify the drainage area where TR-20 peak flow predictions significantly deviate from flow frequency predictions. We developed flow frequency estimates for 130 small-area stream gage sites in rural Nebraska and compared the calculated return period discharges …

Optimizing Nitrogen Management: Assessing Nitrate Transport In The Deep Vadose Zone And Its Impact On Groundwater Quality In East-Central Nebraska, Muili O. Lawal

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Groundwater contamination by nitrate (NO₃-N) is a growing environmental and public health concern driven largely by intensive agricultural fertilizer applications. The vadose zone plays an important role in NO₃-N transport, influencing groundwater quality and agricultural sustainability. This study investigated NO₃-N leaching dynamics in the deep vadose zone of Water Quality Sub-Area 30 (WQA30) within the Lower Loup Natural Resources District (LLNRD), northeast of Columbus, Nebraska (mean groundwater NO₃-N: 20.3 mg/L), using soil cores from 16 shallow (to 6.1 m) and four deep (down to 25.9 m) across four zones, two with inorganic fertilizer (Zones 1 and 4) and two with …