Physical Sciences and Mathematics Commons^™

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 …

Assessing Hydrologic And Water Quality Sensitivities To Precipitation Changes, Urban Growth And Land Management Using Swat, Alexander Michael Psaris

Dissertations and Theses

Precipitation changes and urban growth are two factors altering the state of water quality. Changes in precipitation will alter the amount and timing of flows, and the corresponding sediment and nutrient dynamics. Meanwhile, densification associated with urban growth will create more impervious surfaces which will alter sediment and nutrient loadings. Land and water managers often rely on models to develop possible future scenarios and devise management responses to these projected changes. We use the Soil and Water Assessment Tool (SWAT) to assess the sensitivities of stream flow, sediment, and nutrient loads in two urbanizing watersheds in Northwest Oregon, USA to …

Household Water Demand And Land Use Context: A Multilevel Approach, Elizabeth Yancey Breyer

Dissertations and Theses

Urban water use arises from a mix of scale-dependent biophysical and socioeconomic factors. In Portland, Oregon, single-family residential water use exhibits a tightly coupled relationship with summertime weather, although this relationship varies with land use patterns across households and neighborhoods. This thesis developed a multilevel regression model to evaluate the relative importance of weather variability, parcel land use characteristics, and neighborhood geographic context in explaining single-family residential water demand patterns in the Portland metropolitan area. The model drew on a high-resolution panel dataset of weekly mean summer water use over five years (2001-2005) for a sample of 460 single-family households …

Lifeblood Of The Earth: Nuwuvi (Southern Paiute) Hydrological Knowledge And Perceptions Of Restoration In Two Southern Nevada Protected Areas, Kendra Lesley Wendel

Dissertations and Theses

In the arid landscapes of the southern Great Basin and northern Mojave Desert, issues surrounding water resource management are often politically contentious. Nuwuvi (Southern Paiute) have known and managed these resources for thousands of years prior to Euro-American arrival in the region. A variety of factors, including federal policies that resulted in the creation of reservations and forced placement in boarding schools, as well as contemporary resource commodification, have influenced Nuwuvi knowledge and practice.

In this thesis, I examined the character of Nuwuvi ethnohydrological knowledge, including management knowledge, of two protected areas: Spring Mountains National Recreation Area (SMNRA), managed by …

Development Of A Steady-State River Hydrodynamic And Temperature Model Based On Ce-Qual-W2, Wenwei Xu

Dissertations and Theses

CE-QUAL-W2 is a 2-D hydrodynamic and water quality model that has been applied to reservoirs, lakes, river systems, and estuaries throughout the world. However, when this model is applied for shallow systems, this model requires a long calculation time to maintain numerical stability, compared to applications of reservoirs or deeper river systems.

To solve this problem, a new hydrodynamic and temperature model was built based on the framework of CE-QUAL-W2 but that allows for steady-state hydrodynamic computations. By calculating the hydrodynamics at steady-state, the time step for stability is relaxed and simulations can proceed at much higher time steps. The …

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 …