Other Civil and Environmental Engineering Commons^™

Mixing, Metabolism, And Climate Change: A Modeling Case Study Of A Shallow Hypereutrophic, Polymictic Lake, Benjamin C. Reuss

Dissertations, Master's Theses and Master's Reports

Globally, lakes are sites of significant carbon cycling, respiring an estimated 0.07 to 0.15 Pg as CO2 and sequestering 0.03 to 0.07 Pg C in sediments annually. These processes can be affected by nutrient availability, with seasonal mixing regulating nutrient transport in monomictic and dimictic systems. However, the effect of intermittent mixing on ecosystem production in polymictic systems has been much less studied. The timing and frequency of lake mixing are expected to be altered by climate change, which has the potential to impact nutrient transport. The first chapter of this thesis introduces lake mixing dynamics and indices of mixing. …

Local Watershed Analysis For Hubbell And Lake Linden, Michigan, Brittany Hubbard

Dissertations, Master's Theses and Master's Reports

This report analyzes flood frequency risk, examines drainage, and delineates local level watershed characteristics for the Site located in western HUC 12-040201 030304 Torch Lake Subwatershed. Specifically, unnamed catchments in need of HUC-14 or HUC-16 local level delineation are evaluated to determine the effects of excess runoff on the cities of Hubbell and Lake Linden, Michigan. Further, this report aims to identify the location of known or suspected historical and current drainage infrastructure, and to prioritize locations for low-impact sustainable designs that reduce excess runoff and provide flood protection for these lakeshore communities.

Spatial Analysis Of The Infrastructural Demands Of Integrating 5g Technology: A Case Study In The City Of Detroit, Gregory Putman

Dissertations, Master's Theses and Master's Reports

The invention of 5G technology is expected to revolutionize wireless communication, technology, and capabilities. One major challenge in realizing this vision is the actual deployment of 5G nodes and the development of 5G network infrastructure. Higher frequency and shorter wavelengths that are characteristic of 5G technology is expected to decrease signal range radii of 5G nodes, which could have serious implications for the implementation of a 5G network. This study assessed cell signal density and cell signal coverage that could be achieved using existing 4G infrastructure in the city of Detroit. Results indicate that existing infrastructure is not capable of …

Mechanistic Insight Into The Degradation Of Nitrosamines Via Aqueous-Phase Uv Photolysis Or A Uv-Based Advanced Oxidation Process: Quantum Mechanical Calculations, Daisuke Minakata, Erica Coscarelli

Department of Civil, Environmental, and Geospatial Engineering Publications

Nitrosamines are a group of carcinogenic chemicals that are present in aquatic environments that result from byproducts of industrial processes and disinfection products. As indirect and direct potable reuse increase, the presence of trace nitrosamines presents challenges to water infrastructures that incorporate effluent from wastewater treatment. Ultraviolet (UV) photolysis or UV-based advanced oxidation processes that produce highly reactive hydroxyl radicals are promising technologies to remove nitrosamines from water. However, complex reaction mechanisms involving radicals limit our understandings of the elementary reaction pathways embedded in the overall reactions identified experimentally. In this study, we perform quantum mechanical calculations to identify the …

A Model To Predict Concentrations And Uncertainty For Mercury Species In Lakes, Ashley Hendricks

Dissertations, Master's Theses and Master's Reports

To increase understanding of mercury cycling, a seasonal mass balance model was developed to predict mercury concentrations in lakes and fish. Results indicate that seasonality in mercury cycling is significant and is important for a northern latitude lake. Models, when validated, have the potential to be used as an alternative to measurements; models are relatively inexpensive and are not as time intensive. Previously published mercury models have neglected to perform a thorough validation. Model validation allows for regulators to be able to make more informed, confident decisions when using models in water quality management. It is critical to quantify uncertainty; …

Air Injection As A Scour Countermeasure At Bridge Piers, Ravi Teja Reddy Tippireddy

Dissertations, Master's Theses and Master's Reports

Local scour is a major cause of concern for the stability of bridge piers and the safety of the public using the bridges. Structural countermeasures and flow-altering devices have been developed to deal with local scour. Many armoring structural countermeasures are very effective and efficient in clear water conditions but are susceptible to moving bed forms and leaching. The flow-altering devices are effective in both clear water conditions and moving bed forms, but are prone to clogging, less efficient in changing flow direction, etc. This study aims to reduce the local scour by injecting air in order to reduce the …

Reviews And Syntheses: Ocean Acidification And Its Potential Impacts On Marine Ecosystems, Khan M.G. Mostofa, Cong-Qiang Liu, Weidong Zhai, Marco Minella, David Vione, Kunshan Gao, Daisuke Minakata, Et.Al

Department of Civil, Environmental, and Geospatial Engineering Publications

Ocean acidification, a complex phenomenon that lowers seawater pH, is the net outcome of several contributions. They include the dissolution of increasing atmospheric CO2 that adds up with dissolved inorganic carbon (dissolved CO2, H2CO3, HCO3−, and CO32−) generated upon mineralization of primary producers (PP) and dissolved organic matter (DOM). The aquatic processes leading to inorganic carbon are substantially affected by increased DOM and nutrients via terrestrial runoff, acidic rainfall, increased PP and algal blooms, nitrification, denitrification, sulfate reduction, global warming (GW), and by atmospheric CO2 itself through enhanced photosynthesis. They are consecutively associated with enhanced ocean acidification, hypoxia in acidified …

Designing A Permeable Reactive Barrier For The Remediation Of Copper Contaminated Groundwater., Christopher Walkons

Dissertations, Master's Theses and Master's Reports

This project details the design of a sorption based pilot-scale permeable reactive barrier (PRB) for the removal of copper from groundwater. The reactive material for the barrier is the residual of coagulants used in drinking water treatment operations. Physical and chemical properties of these water treatment residuals (WTR) have been studied to optimize PRB design. Batch reactor tests have shown that equilibrium sorption of copper can be fit to a Langmuir type isotherm. Kinetic and column experiments have been conducted to understand the significance of chemical and physical mass transfer limitations. A leaching test indicated the concentrations of hazardous elements …

A Sustainability-Based Project Selection Algorithm: Socio-Technical-Economic Project Selection (Steps) Algorithm, Bharathi Bhattu

Dissertations, Master's Theses and Master's Reports

Multi-dimensional aspects play a vital role in the task of project-decision making. Environmental effects are to be considered in addition to other technical and non-technical aspects in order to avoid undue environmental damage. This current work introduces a new decision-making algorithm (Socio-Technical-Economic Project Selection or STEPS) that is demonstrated with the use of RCA (recycled concrete aggregate) as riprap for slope stabilization and erosion control which leaches chemical arsenic when in contact with water. Arsenic has long been recognized for its lethal properties. The main intention of introducing this new algorithm is to use sustainability concepts of social, technical, and …

Numerical Study Of Structural Responses Of Rigid And Flexible Pavements Under Heavy Vehicles’ Loading, Rezwana Kabir

Dissertations, Master's Theses and Master's Reports

The highway system serves as the most critical transportation link in the economic development of a nation. In Michigan, about 74% of all the commodities delivered annually are transported by heavy trucks. The Michigan Department of Transportation (MDOT) permits multi-axle (11 axles) heavy truck with gross vehicle weight (GVW) limit of 164,000 lb., unlike many states having GVW limit of 80,000 lb. The effect of these heavy truck loadings on pavements might accelerate the rate of deterioration for flexible and rigid pavement structures. More detailed knowledge of the interaction of trucks with the pavement structure is essential for better management …

The Effect Of Water Temperature On In-Stream Sediment Concentration And Transport Rate, Jennie Tyrrell

Dissertations, Master's Theses and Master's Reports

Global climate change may result in rising temperatures. As a result, ecological health and the human use of rivers may be impacted. The hydrologic cycle, watershed hydrology, and in-stream hydraulics are dynamic systems, influenced by human activities, natural events, and climate. Although known drivers like precipitation and stream velocity govern sediment processes, the effect of water temperature on sediment transport remains unclear. In-stream sediment movement could lead to blocked harbors, flooding, and degradation of vulnerable fish habitat. To better understand how fluctuations in water temperature affect sediment dynamics, six transport models were analyzed on the Niobrara River, with water temperatures …