The snowmelt-dominated Cascade Mountains provide critical water supply for agriculture, ecosystems, and municipalities. Throughout the Pacific Northwest, analyses of projected climate change impacts show rising temperatures resulting in diminished snowpacks, which is expected to lead to declines in summertime in-stream flow. The McKenzie River basin, which is located in the central western Cascades of Oregon, exhibits characteristics typical of many river systems in the western United States. In this watershed, farmers, fish, hydropower, and municipal users compete for a limited supply of water, especially in summer when in-stream flows reach a minimum. Future climate projections anticipate warmer but wetter winters and longer, drier summers, but watershed-scale impacts of these regional projections are not well understood. While snowpack has been measured at the local scale for decades, accurate basin-wide measurements of snowpack do not exist. The lack of basin-scale water supply projections leave water resource managers without decision-support tools to plan effectively in the face of climate change. This doctoral dissertation research project will use a mix of quantitative and qualitative research methods (1) to quantify the basin-wide distribution of snow-water equivalent for the McKenzie River watershed and project distributions of -water equivalent for potential future climate scenarios on the decadal scale; (2) quantify snowpack contributions to streamflow in the upper reaches of the McKenzie River watershed and project impacts on stream flow for potential future climate scenarios on the decadal scale; and (3) design and test the effectiveness of a "hydrologic dashboard" shaped by user input to disseminate scientific information to a broad base of stakeholders.
This research project will provide the first quantitative representation of spatially distributed snow-water equivalent in the Oregon Cascades. It will project future distributions of snow-water equivalent and predict how these impacts will affect stream flow. Because the development of the graphical hydrologic dashboard will be driven by stakeholder input (including federal, state, and local agencies; public utilities; and non-profit organizations), this decision-support tool should improve the accessibility and saliency of the research and provide water resource managers with valuable information. The project should also assist scientists in learning how to better disseminate their research results. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.
