Physical Sciences and Mathematics Commons^™

Testing The Impact Of A Freshwater Wetland Restoration On Water Table Elevation And Soil Moisture Using A Parametric Groundwater Modeling Approach, Erika T. Ito

Masters Theses

Wetlands are now recognized for the many social, environmental, ecological, and economic benefits they provide. They improve water quality, support biodiversity, abate floods and storms, and provide local recreational areas. Historically, many wetlands have been drained or altered for residential, commercial, or agricultural use. Effective wetland restoration projects reestablish ecosystem services and mitigate legacy effects of land use change to create self-sustaining systems. However, a persisting lack of scientifically-vetted methodological and evaluation guidelines in the field of restoration ecology has caused many restoration efforts to fail to restore natural wetland hydrologic conditions. By definition, wetlands must be saturated, permanently or …

Using Low-Flow Sampling Data To Estimate Hydraulic Conductivity In Aquifers, Joy Kiefer

Masters Theses

Hydrogeologists sample wells to test aquifer water quality and use slug tests to estimate aquifer permeability. Robbins et al. (2009) proposed a more efficient way to obtain the goals of the two tests—the use of low-flow sampling and the use of the resulting flow rate and drawdown data to estimate aquifer hydraulic conductivity (K). The Robbins et al. method calculates K by using the slope of the best fit line from the graph of flow rate vs. drawdown for all low-flow pumping data collected at a well. When the method was applied to low-flow data from four Kalamazoo, MI, it …

High-Resolution Timeseries Analysis Of Dynamic Geochemistry: A 27-Well Survey Of Contaminated Groundwater Downstream Of The Former S-3 Ponds, Oak Ridge, Tennessee, Emma Dixon

Masters Theses

Spatiotemporal variability of geochemistry of contaminated groundwater has large implications on overall water quality and ability to respond to remedial applications. Gaining knowledge of how geochemistry changes over time in an area can help establish response trends to changing external conditions like weather and level of contamination. In this study, a spatiotemporal survey was performed on 27 wells at the Y-12 Complex in Oak Ridge, Tennessee. This was completed to measure diurnal fluxes in geochemistry from seasonal changes and extreme weather conditions in three areas of historically different contamination levels from a single point contamination source. Measurements were gathered over …

Hydrologic Structure And Function Of Vernal Pools In South Deerfield, Massachusetts, Charlotte Axthelm

Masters Theses

Vernal pools are small, ephemeral wetlands lacking an inlet or outlet. These wetlands, also known as seasonal pools, are found in a wide range of biomes, and their characteristics vary based on location. While the vegetation of western U.S. pools, and amphibians of eastern U.S. pools have been extensively studied, many aspects of vernal pools have not been fully characterized. In particular, although the general seasonal wetting and drying cycle is understood qualitatively, few studies have attempted to quantify the hydrological regime of vernal pools in New England. As water level variation drives many, if not all, of the characteristics …

An Exploration Into The Controls And Extent Of Capillary Rise In Fine-Grained Sand, Neal S. Turluck

Masters Theses

Capillary rise in fine-grained sands is especially important due to the wide distribution of fine-grained sediment throughout the unconsolidated sedimentary layers blanketing the earth. The height to which water rises above the water table in porous media is known as the capillary fringe. Tension pulling on the water molecules from the solid surfaces of pores will cause water to rise in the unconsolidated fine-grained sands until the water reaches equilibrium with the downward force of gravity.

Researching the controls behind capillary rise and being able to predict the extent to which water will rise in fine-grained sand helped provide insight …

Modeling Channel Response To Dam Removal In Lansing, Michigan, Using Swat, Ryan Filbin

Masters Theses

The removal of dams has increased in recent decades in the United States, largely resulting from decaying infrastructure and greater efforts to restore rivers to a more natural, free-flowing state. Dam removal presents the opportunity for increased public safety, improved environmental prosperity, and improved economic prosperity in conjunction with riverfront revitalization projects. The City of Lansing, Michigan, contains two moderate-to high-risk dams along the Grand River that pose a significant risk to the surrounding area in the event of structural failure.

The Soil and Water Assessment Tool (SWAT) is applied to model the impacts of the Moores Park Dam and …

Characterizing Groundwater Recharge And Streamflow Using Stable Isotopes Of Oxygen And Hydrogen, Chanse M. Ford

Masters Theses

Potential changes to climate and precipitation patterns from anthropogenic influences like global climate change could have an impact on Michigan’s groundwater resources. Indirectly this could have an effect on Michigan’s surface waters as well, since groundwater and surface waters are intimately linked to form one system.

This investigation utilized stable isotopes of oxygen and hydrogen found in precipitation, groundwater and surface waters to better understand the contribution of different types of precipitation to recharge of a shallow aquifer in Manistee National Forest, MI. The study also examines the contribution of this shallow groundwater to streamflow in the nearby White River. …

Sources Of Water And Solutes To The Salar De Atacama, Chile: A Coupled Hydrologic, Geochemical, And Groundwater Modeling Study, Lilly G. Corenthal

Masters Theses

Focused groundwater discharge in endorheic basins provides opportunities to investigate mechanisms for closing hydrologic budgets in arid regions. The Salar de Atacama (SdA), a closed basin in northern Chile, has accumulated over 1800 km³ of halite and a lithium-rich brine since the late Miocene primarily through evapotranspiration of groundwater. The hydrologic balance of SdA and sources of water and solutes required to explain this deposit are not well constrained. An adapted chloride mass balance method drawing on a database of over 200 water sample sites is applied to a remotely-sensed precipitation dataset to estimate spatially-distributed modern groundwater recharge. Comparing …

Impacts Of Three-Dimensional Non-Uniform Groundwater Flows For Quantifying Groundwater-Surface Water Interactions Using Heat As A Tracer, Jonathan M. Reeves

Masters Theses

Heat-as-a-tracer has become a common method to quantify surface water-groundwater interactions (SW/GW). However, the method relies on a number of assumptions that are likely violated in natural systems. Numerical studies have explored the effects of violating these fundamental assumptions to various degrees, such as heterogeneous streambed properties, two-dimensional groundwater flow fields and uncertainty in thermal parameters for the 1-dimensional heat-as-a-tracer method. No work to date has addressed the impacts of non-uniform, three-dimensional groundwater flows on the use of heat-as-a-tracer to quantify SW/GW interactions. Synthetic temperature time series were generated using COMSOL Multiphysics for a three-dimensional cube designed to represent a …

Determining Discharge From The Fallasburg Dam And The Hydrology Of The Flat River Bypass Channel, Lowell, Michigan, Seth Kuiper

Masters Theses

The Fallasburg Dam on the Flat River is required to release 110 cfs to the Bypass Channel. Residents have often reported low flows in the river, especially during the summer. The hydrology of the Bypass Channel downstream from the dam was investigated to determine whether the required flow was being released. Discharge measured at multiple transects reveal a shifts from gaining to losing conditions during the year. Gaining conditions occur during the spring and after significant rain events; losing conditions occur in the summer during dry periods. Five discharge measurements in 2013 and three in 2014 reveal flows less than …