Earth Sciences Commons^™

Scenes From The Swale: Investigating Spatial And Temporal Dimensions Of Nitrogen Cycling In Urban Stormwater Bioretention Facilities, Erin Nicole Looper

Dissertations and Theses

Urban development is transforming landscapes at unprecedented rates. Human activities and landscape modifications associated with urbanization extensively increase hydrologic demands and modify natural hydrologic systems; consequently, population growth occurring in urban areas increases pressure on water resources. Urban aquatic ecosystems are vulnerable to impacts associated with increased connectivity with urban surfaces and hydrologic changes that initiate long-term changes in receiving waterbodies. Nitrogen (N) loading from urban and suburban catchments to receiving surface waters can lead to impairment of aquatic ecosystems and is a concern in many cities with water quality issues. To improve urban water quality, cities are increasingly adopting …

Rock Glaciers Of The Contiguous United States: Spatial Distribution, Cryospheric Context, And Riparian Vegetation, Gunnar Forrest Johnson

Dissertations and Theses

Continental-scale inventories of glaciers are available, but no analogous rock glacier inventories exist. We present the Portland State University Rock Glacier Inventory (n = 10,343) for the contiguous United States, then compare it to an existing inventory of contiguous United States glaciers (n = 853), identifying geographic and climatic factors affecting the spatial distributions observed. At least one rock glacier is identified in each of the 11 westernmost states, but nearly 90% are found in just five; Colorado (n = 3889), Idaho (n = 1723), Montana (n = 1780), Utah (n = 834), and Wyoming (n = 849). Glaciers are …

Soil Phosphorus Characterization And Vulnerability To Release In Urban Stormwater Bioretention Facilities, Benjamin James Shetterly

Dissertations and Theses

Modern urban stormwater infrastructure includes vegetated bioretention facilities (BRFs) that are designed to detain water and pollutants. Phosphorus (P) is a pollutant in stormwater which can be retained in BRF soils in mineral, plant, and microbial pools. We explored soil properties and phosphorus forms in the soils of 16 operational BRFs in Portland, OR. Since soil hydrology can significantly impact P retention, we selected BRFs along an infiltration rate (IR) gradient. We conducted sequential fractionation and tests of P pools and measured P release in a subset of soils after drying and flooding samples for ten days. We hypothesized that …

Turbidity Dynamics During High-Flow Storm Events In The Clackamas River, Oregon 2006-2012, Micelis Clyde Doyle

Dissertations and Theses

Turbidity is a useful parameter that can be utilized to help understand the water quality in a river and is an expression of the optical properties of a liquid that cause light rays to be scattered and absorbed rather than transmitted in straight lines. A total of 41 storm events occurring during water years 2006-2012 were analyzed for this study. A hysteresis index (HI) was used to assess the difference in turbidity on the rising and falling limbs of a storm-hydrograph. The upstream Carter Bridge site exhibited a clockwise (C) hysteresis in 38 of 41 storm events and counter-clockwise (CC) …

Analyzing Dam Feasibility In The Willamette River Watershed, Alexander Cameron Nagel

Dissertations and Theses

This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. Constructed between 1941 and 1969, these structures function in collaboration to comprise the Willamette River Basin Reservoir System (WRBRS). The motivation for this project derives from a growing awareness of the biophysical impacts that dam structures can have on riparian habitats. This project compares each of the 13 dams being assessed, to prioritize their level of utility within the system. The study takes the metrics from the top …

A Numerical Model Investigation Of The Role Of The Glacier Bed In Regulating Grounding Line Retreat Of Thwaites Glacier, West Antarctica, Michael Scott Waibel

Dissertations and Theses

I examine how two different realizations of bed morphology affect Thwaites Glacier response to ocean warming through the initiation of marine ice sheet instability and associated grounding line retreat. A state of the art numerical ice sheet model is used for this purpose. The bed configurations used are the 1-km resolution interpolated BEDMAP2 bed and a higher-resolution conditional simulation produced by John Goff at the University of Texas using the same underlying data. The model is forced using a slow ramp approach, where melt of ice on the floating side of the grounding line is increased over time, which gently …

Groundwater-Surface Water Interactions Near Mosier, Oregon, Cullen Brandon Jones

Dissertations and Theses

The town of Mosier, Oregon, is located near the east, dry end of the Columbia River Gorge, and the local area is known for cherry orchards that rely heavily on groundwater for irrigation. The CRBG groundwater system in Mosier has experienced groundwater declines of up to 60 meters due to over-pumping and or commingling. Declining groundwater levels have led to concerns over the sustainability of the resource, as it is the principle water source for irrigation and domestic use. Despite numerous previous studies of groundwater flow in CRBG aquifers here and elsewhere in the Columbia River basin, an aspect that …

The Terroir Of Pinot Noir Wine In The Willamette Valley, Oregon : A Broad Analysis Of Vineyard Soils, Grape Juice And Wine Chemistry, Kathryn Nora Barnard

Dissertations and Theses

Terroir is determined by a combination of factors in the vineyard including the grape varietal, geology and soil, soil hydrology, physiography, and climate. Although most studies have examined regional differences in wine flavors and associated provenance of wine based on chemistry, few have examined the chemistry of the soil and the ability to trace that chemistry to grape juice and, finally, to the wine. This dissertation examines what soil physical and chemical differences specific to this region might influence grape juice chemistry and wine chemistry.

Wine-grapes in the Willamette Valley, Oregon, are grown on three major soil parent materials: volcanic, …

Investigating The Link Between Surface Water And Groundwater In The Tule Lake Subbasin, Oregon And California, Esther Maria Pischel

Dissertations and Theses

Water allocation in the upper Klamath Basin of Oregon and California has been challenging. Irrigators have increasingly turned to groundwater to make up for surface water shortages because of shifts in allocation toward in-stream flows for Endangered Species Act listed fishes. The largest increase in groundwater pumping has been in and around the Bureau of Reclamation's Klamath Irrigation Project, which includes the Tule Lake subbasin in the southern part of the upper Klamath Basin. Previous groundwater flow model simulations indicate that water level declines from pumping may result in decreased flow to agricultural drains in the Tule Lake subbasin. Agricultural …

Streamflow Modeling Of Johnson Creek Subwatersheds Using The Precipitation Runoff Modeling System, Theophilus Matthew Malone

Civil and Environmental Engineering Master's Project Reports

Johnson Creek, in the Portland, Oregon metropolitan region, has several pollutants on the U.S. Environmental Protection Agency's (EPA) 303(d) list including excess heat, low dissolved oxygen, and harmful bacteria. Understanding streamflow response to precipitation events is an important component to evaluating water quality trends and calculating the Total Maximum Daily Load (TMDL) for pollutants of concern. Investigating the streamflow-precipitation relationship on the subwatershed scale can give insight to the hydrologic response of a given watershed. However, developing rating curves for several subwatersheds can be cost and time prohibitive. The objective of this project was to develop a hydrologic model using …

Towards Improving Drought Forecasts Across Different Spatial And Temporal Scales, Shahrbanou Madadgar

Dissertations and Theses

Recent water scarcities across the southwestern U.S. with severe effects on the living environment inspire the development of new methodologies to achieve reliable drought forecasting in seasonal scale. Reliable forecast of hydrologic variables, in general, is a preliminary requirement for appropriate planning of water resources and developing effective allocation policies. This study aims at developing new techniques with specific probabilistic features to improve the reliability of hydrologic forecasts, particularly the drought forecasts. The drought status in the future is determined by certain hydrologic variables that are basically estimated by the hydrologic models with rather simple to complex structures. Since the …

Characterization Of The Shallow Subsurface Geohydrology Of The Ni-Les'tun Unit On The Bandon Marsh National Wildlife Refuge, Christopher Madison Beard

Dissertations and Theses

The Bandon Marsh is a large marsh restoration project located in southwest Oregon. The land has been previously used for dairy farms and much of the marsh was used for cattle grazing. The goal of the restoration is to recreate a natural habitat for shorebirds and fish. The purpose of this thesis is to gather and analyze data on the geology of the marsh and both ground and surface water quality to evaluate its ability to support biology.

The US Fish and Wildlife Service began restoration on the Bandon marsh in 2005. Research on the Ni-les'tun Unit began in that …

Arsenic Mobility And Compositional Variability In High-Silica Ash Flow Tuffs, Courtney Beth Young Savoie

Dissertations and Theses

Volcanic rocks typically have only low to moderate arsenic concentrations, none-the-less, elevated levels of arsenic in ground waters have been associated with pyroclastic and volcaniclastic rocks and sediments in many parts of the world. The potential for arsenic leaching from these deposits is particularly problematic as they often comprise important water-bearing units in volcanic terrains. However, the role that chemical and mineralogical variations play in controlling the occurrence and mobility of arsenic from pyroclastic rocks is largely unexplored.

This study uses chemical and X-ray diffraction data to characterize and classify 49 samples of ash-flow tuffs, and 11 samples of tuffaceous …

Map-Based Probabilistic Infinite Slope Analysis Of The Stephens Creek Watershed, Portland, Oregon, Ryan Andrew Cole

Dissertations and Theses

The Stephens Creek Watershed in southwest Portland, Oregon was chosen by the city as a pilot project for urban stream restoration efforts, and the infiltration of stormwater was identified as a potential restoration strategy. The Stephens Creek Watershed has historically been known to be unstable during high precipitation events (Burns, 1996), and the need to address the response of slope stability to anthropogenically-driven changing groundwater conditions is the focus of this study. Airborne light detection and ranging (LiDAR) and geotechnical data from the City of Portland were employed to create a high resolution (0.84 m2) physics-based probabilistic slope stability model …

Calculating The Volume Of The May 18, 1980 Eruption Of Mount St. Helens, Dâvid Nuñez Wickham

Environmental Science and Management Professional Master's Project Reports

The May 18, 1980 eruption of Mount St. Helens created a massive amount of sediment and debris, thought to be as much as 5.5 billion cubic yards. This sediment causes infill of river stretches and collects along levees protecting southwest Washington State. The sediment must be removed to ensure these areas do not flood. The US Army Corps of Engineers (USACOE) is tasked with flood protection for southwest Washington State and the levees protecting the cities of Castle Rock, Lexington, Kelso, and Longview. The Sediment Retention Dam, opened in 1989 is able to filter out larger particulate but fine grain …

Post-Middle Miocene Geologic History Of The Tualatin Basin, Oregon With Hydrogeologic Implications, Doyle Coley Wilson

Dissertations and Theses

The geologic history and sedimentary till of the Tualatin Basin after Columbia River Basalt Group (CRBG) emplacement is assessed and related to groundwater characteristics. The 334 m deep HBD-1 core from the Hillsboro Airport, provides the primary information for sediment characterization and is supported by over 2400 well logs and cores, and four seismic lines. The sedimentary section above the 26 m thick paleosol on the CRBG in HBD-I is divided into two main groups: a 25 m thick section of Missoula flood sediments called the Willamette Silt overlies a 263 m thick finegrained sequence of fluvial Neogene sediments.

Pollen, …

Hydrogeochemical Characterization Of The Alvord Valley Known Geothermal Resources Area, Harney County, Oregon, Anna Maria St. John

Dissertations and Theses

The Alvord Valley Known Geothermal Resources Area (KGRA) , located east of the Steens Mountain-Pueblo Mountains fault block in southeastern Oregon, is within the northern Basin and Range province. This investigation focuses on three thermal areas in the Alvord Basin: Borax Lake and the hot springs north of Borax Lake, Alvord Hot Springs and Mickey Springs.

Mickey Springs and the springs north of Borax Lake are boiling at the surface (94 and 95° C, respectively). Inflow temperatures to Borax Lake, measured at a depth of 30 m, are greater than 100° C. Surface temperatures for Alvord Hot Springs and a …

Preliminary Investigation For Underground Storage Of Pipeline Gas In The Bruer And Flora Pools, Mist Gas Field, Columbia County, Oregon, Paul Joseph Townley

Dissertations and Theses

Northwest Natural Gas Canpany has proposed to convert the Bruer and Flora pools of the Mist Gas Field in west-central Columbia County, Northwestern Oregon, to pipeline gas storage reservoirs. Conversion to underground storage of pipeline gas in these depleted gas reservoirs would be the first in the Pacific Northwest. The Bruer and Flora Pools are fault trapped within the Cowlitz Formation. The shales overlying the Cowlitz Formation create a local seal for these gas reservoirs. X-ray diffraction and density log measurements suggest that the clay in these shales is primarily composed of smectite, which provides an excellent caprock seal.

The …