Hydrology Commons^™

Quantifying The Impacts Of Land Use And Land Cover Change On Urbanizing Agricultural Systems, Carli Beisel

Boise State University Theses and Dissertations

Western water supplies are increasingly stressed by the compounding impacts of population growth, urbanization, and climate change. Rising temperatures in Idaho are shifting precipitation patterns, with more falling as rain rather than snow. This reduces snowpack and the resulting snowmelt, which serves as the predominant water source for agriculture. At the same time, urbanization of agricultural land decreases surface permeability, replaces irrigated fields, and amplifies the impacts of climate change. The Treasure Valley, located in southwestern Idaho, has been rapidly urbanizing; urban land cover has grown by 52% from 1985 to 2021. Understanding how land use and land cover changes …

Unraveling Snow And Rain Contributions To Streamflow Through A Methodological Investigation On Cold And Warm Season End-Members, Rachel Grena

Boise State University Theses and Dissertations

Water supply and demand are encountering unique challenges in the western United States as climate change impacts the availability of water resources. Much of the west relies on high mountain snowpack to maintain consistent streamflow throughout the dry, warm season months. Temperatures often rise above freezing in the cold season, diminishing the snowpack size, and altering the timing of snowmelt. As droughts become more frequent, water managers are increasingly concerned about the risk of reduced summer streamflow. To understand changing hydrologic patterns, this study utilizes phase changes in precipitation, specifically the distinction between cold and warm season precipitation, and their …

Effects Of Changing Winter Precipitation Phase On Streamflow Magnitude In Mountainous Regions, Josh Morell

Boise State University Theses and Dissertations

Snowmelt-produced streamflow (Q) is the dominant water source for a large portion of the global population. This is especially true in higher elevation regions in the Western United States. Precipitation is highly variable and seasonal in this region of the world. Generally, most precipitation occurs in winter and comes as snow in higher elevations. However, due to climate change, precipitation and temperature patterns are changing. It has been observed in many areas across the Western United States that the fraction of precipitation falling as snow (S_f) is declining because of a warming climate. In addition, …

Radiogenic Isotope And Ionic Concentration Ratios Reveal Hydrologic Mixing, Subsurface Residence Time, And Cross-Basin Transfer In A Snow-Fed Mountain Karst Watershed, Nathaniel Ashmead

Boise State University Theses and Dissertations

Snow-fed karst aquifers support various complex ecosystems and provide a vital water source to communities worldwide. Due to their nature and distribution, these watersheds may be particularly vulnerable to the effects of climate change. Water resource managers can mitigate uncertainty from climate impacts with accurate predictions of future water availability provided by hydrologic models. While many such models exist, their effectiveness at predicting streamflow in snow-fed karst watersheds is limited by a lack of insight into the significance of cross-basin groundwater transfers. This study used radiogenic isotope and ionic concentration ratios as natural tracers to detect cross-basin transfer between two …

Climate And Channel Morphology Control Stream Drying Across Scales, Mac Beers

Boise State University Theses and Dissertations

Over half of the global stream network is estimated to dry for at least one day of the year. Streams that dry at some point in space and time are considered intermittent. Intermittent streams exhibit one of three hydrologic states: flowing, non-flowing pools, and dry. The distribution and extent of completely dry channel and non-flowing pools is important for water quality and ecology, however, we are currently unable to accurately predict when, where, and how streams dry at small scales. Few studies have investigated the stream characteristics that influence local scale controls of drying, and more work is needed to …

Agricultural Irrigation Water Quality In The Lower Boise River Basin: A Quantitative Assessment Of Canal Ecosystem Metabolism And Escherichia Coli Spatiotemporal Variability, Reed Chasmar

Boise State University Theses and Dissertations

Irrigation canals are pervasive in agricultural landscapes. Despite their vast spatial extent and significant volumetric impact on the hydrologic cycle, the role of irrigation canals as intermittent channels within a river network, as well as their various functions (e.g., supporting aquatic ecosystems, transporting microbial communities, altering the carbon cycle), are not well understood. Microbial water quality and aquatic ecosystem metabolism represent two mechanisms to assess stream channels that can provide new insights into the complex dynamics and spatiotemporal patterns that exist in irrigation canals, which has relevance for both human health and for the field of stream ecology. The goal …

The Drying Of Dry Creek: A Paired Catchment Experiement Assessing Non-Perennial Headwater Streams, Elizabeth Crowther

Boise State University Theses and Dissertations

Intermittent streams make up the majority of waterways in the United States and are becoming more common in a changing climate, yet they lack stream gaging and habitat data compared to their perennial counterparts. Headwater streams in the western US can be classified as intermittent through seasonal contraction of flowing streams. Although small, they provide critical habitat for fish species and contribute to larger downstream systems. Predictive models, such as the Probability of Stream Permanence (PROSPER) model, have been created to map dry and intermittent reaches at the regional scale, yet they lack large-scale spring data sets as inputs for …

Influence Of Urbanization And Climate On Irrigation Diversions And Return Flows In The Lower Boise River Basin, Bridget Bittmann

Boise State University Theses and Dissertations

The western US is facing both the rapid urbanization of agricultural lands and a changing climate, producing subsequent changes to irrigation water demand and availability. Adaptive water management requires knowledge regarding how and why water usage and availability is changing; however, managers often do not possess the tools or resources for the necessary analysis. These environmental changes are also place-based, meaning that water managers cannot directly use studies from other basins to actively manage theirs. Co-produced, actionable research can help fill this knowledge gap and provide the necessary information for adaptive management. The Lower Boise River Basin (LBRB) in southwestern …

Characteristics Of Stream Source Water Contributions And Associated Geochemical Signatures Along A Climate And Vegetation Gradient In A Glacierized Landscape, Southcentral Alaska, Hannah K. Richardson

Boise State University Theses and Dissertations

Mountain-derived snow and ice melt are essential for global water resources, and over one-sixth of the population depends on melt for freshwater. Rising air temperatures are causing vegetation to replace snow- and ice-covered landscapes and precipitation regimes to change. Collectively, these changes will alter the hydrology of mountain environments, although the exact impacts to hydrologic regimes are poorly understood. The source waters of streamflow (i.e. the proportion of ice melt, snowmelt, rain, and groundwater) dictate the timing and magnitude and affect temperature, sediment, and nutrient fluxes. By examining differences in source waters across basins with varying land covers and precipitation …

Hydrologic Implications Of Snow-Vegetation Interactions In A Semiarid Mountain Climate, Maggi Kraft

Boise State University Theses and Dissertations

Knowledge of the complex interaction between snow, vegetation, and streamflow in semiarid mountain climates is necessary for predicting water resources. The effects of warming temperatures on snow distribution will cascade into vegetation water use and streamflow. Due to our reliance on snow water resources, it is necessary to understand how vegetation affects snow distribution, how vegetation uses snow water inputs and the subsequent effects on streamflow in the current and warming climate. The overall objective of this research is to improve our understanding of snow-vegetation interactions in a semiarid climate. In this dissertation, I use field data to evaluate how …

Application Of A High-Resolution Climate Model Dataset To Assess Habitat Suitability For Spotted Wing Drosophila In Southwest Idaho, Elizabeth Padian

Boise State University Theses and Dissertations

As global climate change continues to produce large deviations from the normals of the 19th and 20th centuries, the agricultural sector will need to adapt to these changes in order to maintain yields and feed the global population. Crop selections, yield amounts, and pest management techniques may need to be adjusted to adapt. The Spotted Wing Drosophila (SWD) is a small fruit fly-like bug that can infest berries and stone fruit crops by burrowing into the fruit (at most points in the fruit’s lifecycle) and laying its eggs. These eggs will hatch and the larvae will burrow back out of …

From River Channel To Cloud Tops: Evaluation And Applications Of Regional Climate Models In Mountain Watersheds, William J. Rudisill

Boise State University Theses and Dissertations

Mountain ranges are vital ”water towers” of the world and are uniquely threatened by anthropogenic climate change. At the same time, the paucity of observing networks limits our understanding of hydrometeorological processes in water-resource critical regions, including the Western United States. In the past decade, non-hydrostatic, convection permitting ( 1-4km horizontal resolution) regional climate models (RCMs) have emerged as a promising tool for both reconstructing regional scale mountain hydroclimates, and for forecasting the impacts of climate perturbations on watersheds and water-resources. Still, challenges remain. To-date, computational and data storage limitations have generally precluded many RCM studies to a handful of …

Exploring Hydrologic Responses To Different Wildfire Spatial Patterns Through The Lens Of Computational Modeling, Luke M. Telfer

Boise State University Theses and Dissertations

Severe wildfire disturbances are becoming increasingly common in high-elevation forests of the western United States. These fires alter watershed hydrologic processes, threatening critical downstream water resources and aquatic ecosystems. However, watershed-scale postfire hydrologic responses and water balance changes are highly uncertain. While postfire effects on individual processes such as runoff, infiltration, evapotranspiration, and snow dynamics are relatively well known, the role of wildfire spatial patterns in governing hydrologic connectivity and interactions between water balance components is poorly understood due to challenges associated with measuring and comparing fires at large scales. This thesis aims to examine pattern-related postfire interactions between various …

Water Quality Responses To A Semi-Arid Beaver Meadow In Boise, Idaho, Luise Bayer Winslow

Boise State University Theses and Dissertations

Beavers have been instrumental in shaping the North American riverine landscape. However, land use change and beaver trapping have caused large decreases in beaver populations, resulting in fundamental changes to river morphology, hydrology, and biogeochemical function. Effective river restoration and remediation of arid western rivers relies on a comprehensive interpretation of how beaver activity influences water quantity and quality. In this study, I compared two stream reaches with and without beaver dams in a semi-arid watershed, to quantify the effects of beaver activity on hydrology and biogeochemistry. Within each reach, I combined dilution gauging and stream tracer experiments to determine …

Laboratory Measurement Of Electrical And Hydraulic Properties Of Regolith Over Granitic Bedrock, Taylor James Bienvenue

Boise State University Theses and Dissertations

Characterizing water flux within the critical zone (CZ) is essential for a multitude of studies and applications related to irrigation, drainage, water management, and contaminant transport. Trying to measure water flux in the critical zone, specifically in the subsurface, is difficult due to the associated structural heterogeneity and complex interactions taking place between biological, chemical, and physical processes. Current methods (i.e., inferred from soil suction and soil moisture measurements) to characterize water flux within the critical zone can be time consuming and are not directly related to water flux. Recent literature has provided evidence that self-potential (SP) is a promising …

Assessment Of Icesat-2 Level 3a Products For Snow Depth Estimation In Remote, Mountainous Watersheds, Colten Michael Elkin

Boise State University Theses and Dissertations

Seasonal snowpack accounts for ~70% of the water supply in the western United States, and measuring snow accumulation and ablation remotely has long been a stated goal of NASA. The 2018 launch of ICESat-2, a spaceborne Lidar system, has offered unparalleled spatial and temporal coverage of mountainous terrain with the potential for unprecedented vertical accuracy. Data from ICESat-2 are used to measure seasonal snow depths using the level-3A ATL08 (land and canopy elevation) product for the Reynolds Creek Experimental Watershed in southwest Idaho and the ATL06 (land ice elevation) product for Wolverine Creek in the Kenai Mountains of Alaska. The …

Using Remote Sensing Data Fusion Modeling To Track Seasonal Snow Cover In A Mountain Watershed, Allison N. Vincent

Boise State University Theses and Dissertations

Seasonal snowfall is the largest component of the water budget in many mountain headwater regions around the world. In addition to sustaining biological water needs in drier, lower elevation areas throughout the year, mountain snowpack also provides essential water inputs to the Critical Zone (CZ) - the outer layer of the Earth’s surface, which hosts a variety of biogeochemical processes responsible for transforming inorganic matter into forms usable for life. Water is a known driver of CZ activity, but uncertainty exists in its spatial and temporal interactions with CZ processes, particularly in the complex terrain of heterogeneous mountain areas. Increasing …

The Signal Of Modern To Holocene Drivers Of Complex Channel Response Of A Small Alluvial Stream, Scott D. Ducar

Boise State University Theses and Dissertations

Small alluvial streams (~100km² drainage area) are important for water resources and aquatic habitat. Small streams throughout the Western United States are impacted by anthropogenic land-use including urban development, mining, logging, beaver trapping, grazing, and farming. Land-use change can trigger a complex series of channel response (such as stream channel incision or channel migration) that vary spatially and temporally in the watershed. However, streams also respond to other external forcings, such as tectonically or climatically-driven changes in discharge or base-level, which make disentangling the drivers of channel response complicated. Therefore, it is important to place modern channel changes into …

Applications Of Continuous Snowpack Temperature Monitoring, Peter J. Youngblood

Boise State University Theses and Dissertations

Predicting metamorphism within seasonal snowpacks is critical for avalanche forecasting and runoff timing as it relates to water supply management. Snowpack temperature gradients play a key role in snow metamorphism, and their magnitude controls how snow strength changes; therefore, they are of interest to avalanche forecasters. Before major melt, the snowpack must warm to isothermal conditions at 0°C. Measuring this transition from warming to the ripening phase could help improve our current models for runoff timing. Measuring snowpack temperature gradients is currently a non-automated process that requires disturbance of the snow profile, and only gives a snapshot in time of …

A 30-Year Agroclimatic Analysis Of The Snake River Valley American Viticultural Area - Descriptive And Predictive Methods, Charles L. Becker

Boise State University Theses and Dissertations

Climate change poses serious threats to global agriculture, however some localities and crops may benefit from increasing temperatures. Grape production in southern Idaho may be a beneficial example as vineyard acreage has increased over 300% since the designation of the Snake River American Viticultural Area (SRVAVA) in 2007. We perform a statistical characterization of agroclimate within the SRVAVA that centers around four primary objectives: utilization of a novel, 30-year high resolution climate dataset to provide insight and agrometrics unavailable at coarser resolutions, climatic implications of the unique topography within the SRVAVA, identification of statistical trends, and correlation of SRVAVA climate …

The Spatial Distribution Of Elevated Uranium In The Treasure Valley Aquifer System, Southwest Idaho, Lloyd A. Womeldorph

Boise State University Theses and Dissertations

The Treasure Valley Aquifer System (TVAS) in southwestern Idaho contains well-documented uranium concentrations over the U.S. Environmental Protection Agency maximum contaminant level of 30 µg/L. With a population in the Treasure Valley projected to reach 1.6 million by 2065, in-depth horizontal and vertical spatial knowledge of the contaminant is needed. This study evaluates the horizontal and vertical spatial nature of uranium in the TVAS and interprets those observations to provide both a conceptual model of uranium behavior, and recommendations for water resource management. A large water quality dataset was compiled, and supplemented by data collected during a field sampling campaign, …

Does The Urbanization Of Agricultural Land Lead To More Or Less Evapotranspiration?, Curtis Ryan Crandall

Boise State University Theses and Dissertations

Agricultural areas within the western U.S. are undergoing rapid urbanization due to population growth. Urban expansion often forces the conversion of adjacent agricultural areas altering the landscape vegetation and associated water consumption through evapotranspiration (ET). The associated difference in ET may alter the landscape water demand complicating water resource management. To investigate these differences, we calculated the agricultural and urban seasonal ET rates in a semiarid watershed currently undergoing large population growth and rapid urbanization. We used high resolution satellite imagery with a GIS computer model to generate basin-wide ET estimates over a 204-day irrigation season. Six land type samples …

Cross-Scale Interactions Between Atmospheric And Hydrologic Processes In A Topographically Complex, Snow-Dominated Watershed As Revealed Through An Integrated Hydrologic Model, Miguel A. Aguayo Arias

Boise State University Theses and Dissertations

In much of the world, water for agricultural, domestic, and hydroelectric power generation uses are derived from snow-dominated mountain basins. In these regions, water management requires accurate and timely knowledge of runoff generation by snowmelt. This information is used to plan reservoir releases for downstream users and is generated by models of biophysical processes associated with varying degrees of fidelity to physical processes and/or spatial heterogeneities. The large variability in the characteristic spatial and temporal scales of atmospheric forcings, land-surface water and energy balance, and groundwater flow contribute to significant uncertainties in resolved hydrologic states and fluxes. Underlying sources of …

Correlating The Spatial Distribution Of Snow Depth To Forest Canopy Parameters Derived From Terrestrial Laser Scans, Zachary Uhlmann

Boise State University Theses and Dissertations

In nonpolar, cold climate zones, snow accounts for 17% of the total terrestrial water storage. Estimating the amount of water stored in a snowpack, the snow water equivalent (SWE), and its spatial distribution is crucial to providing water managers with parameters to predict runoff timing, duration and amount. Reservoir management, hydropower and flood forecasting depend on SWE estimates. While landscape features such as aspect and slope are dominant controls on radiative energy in non-forested areas, forest cover can shift the energy balance composition from turbulent exchange in exposed, windy sites to primarily radiative inputs in the subcanopy. Additionally, forest cover …

Investigating The Annual Water Balance Of A High-Altitude Watershed Using Near-Real Time Lidar Data Integration Into A Physically Based Snowmelt Model, Andrew R. Hedrick

Boise State University Theses and Dissertations

Knowledge of the amount of water stored in the mountain snowpack is crucial for flood prevention, drought mitigation, and energy production in the Western United States. In modeling terms, the most important component of the hydrologic water balance is the precipitation input to the system. Determining where and how much precipitation falls in mountain catchments, however, is the most difficult problem with regards to closing the water balance. The work presented in this dissertation details the modeling portion of the NASA Airborne Snow Observatory (ASO) using the iSnobal physically based snow model. This combination of remote sensing and modeling at …

Evaporation Depth Controls The Relationship Between Soil Water Mobility And Soil Water Isotopic Composition, John Byars Shuler

Boise State University Theses and Dissertations

Recent studies of plant water uptake assume that soil water isotopic composition can be used to infer soil water mobility. However, the strength of the relationship between mobility and isotopic composition remains poorly constrained. In addition, many ecohydrologic investigations are restricted by low sampling frequencies and insufficient soil moisture and matric potential data to support assumptions of soil water mobility. We sampled bulk soil water every 14 to 21 days in hillslope and riparian profiles during the 2016 and 2017 growing seasons in a semi-arid watershed outside Boise, ID. We collected twig samples of four tree and shrub species concurrently. …

Exploring The Role Of Deforestation On Regional Hydroclimate In Southeast Africa: An Approach Fusing Models And Data, Megan Maksimowicz

Boise State University Theses and Dissertations

Land cover acts as the gatekeeper to incoming and outgoing energy and water fluxes at the land surface, partitioning energy and water in accordance with the vegetation type and in response to atmospheric forcings. As Land Surface Models become more complex and more capable of simulating the coupled dynamics of the land-atmosphere system in greater spatial detail, the need for accurate representation of spatial distribution of vegetation types and their dynamics through time grows.

As humans modify land cover, there are complex dynamics at play between the vegetation, the surface energy balance and the cycling of water. The resultant hydroclimatic …

Assessment Of Snow Atmosphere Forcing During Central Idaho Atmospheric Rivers, William Rudisill

Boise State University Theses and Dissertations

Atmospheric Rivers (AR) are globally occuring weather features and the primary mechanism through which water vapor moves from the tropics and subtropics towards the mid-latitudes, doing so at rates comparable to the world’s largest terrestrial rivers. AR that encounter mountains often cause extreme precipitation in the form of rain and snow, high winds, and flooding in many watersheds. They account for as much as 20-30% of cool season precipitation in the central Idaho Mountains. In the Northern Hemisphere, seasonal snow cover during Winter and Spring months is the most variable land surface component in space and time, and acts on …

From Snow To Flow: Exploring Relationships Between Snotel Ablation Curves And Peak Streamflow Timing, Kara Jane Ferguson

Boise State University Theses and Dissertations

Predictions of peak streamflow timing in snow-dominated river systems are essential for proper water management and recreational availability. This study evaluates historic snow and streamflow data from 14 river basins throughout Idaho to investigate the relationship between snowmelt timing at SNOw TELemetry (SNOTEL) sites and peak streamflow within each basin. The goal is to provide a simple operational tool that estimates the probability of peak streamflow occurring within a certain number of days as ablation progresses from 0 to 100% melted. For individual basins we evaluate meltout levels in increments of 10% from each SNOTEL site and use a probabilistic …

Using Landlab, A Fine Scale Biogeography Model, To Measure The Sustainability Of Semi-Arid Vegetation In A Changing Climate, Lucy Gelb

Boise State University Theses and Dissertations

The distribution of vegetation in water-limited ecosystems is a product of complex and nonlinear interactions between climatic forcings (e.g., precipitation, temperature, solar radiation) and the underlying geomorphic template, which includes topography, geology, and soils. Changes in climate, particularly in precipitation and temperature, can dramatically alter the organization of vegetation. This is especially true in ecotones such as our area of study: the semi-arid transition between Great Basin shrub-steppe ecosystems and the coniferous forests of the Northern Rockies. Understanding and predicting how the spatial composition of terrestrial vegetation communities will change in these ecosystems is critical to predicting important future landscape …