This study examines the role of politics in the removal of the 106-foot tall San Clemente Dam. The removal project and negotiations provide a case study of the contemporary phenomenon of dam removal. My analysis joins a growing body of social science literature on the social, political, and human dimensions of removal. The San Clemente Dam, which impounded the Carmel River near Monterey, California, was removed in 2015, the largest such project completed in California. Drawing on political ecology and science and technology studies, and using a mixed qualitative approach, I assess both the role of politics in shaping the project and the politics affected through or by the removal. I use a broad, historically attentive analysis of the region to contextualize the political elements of the project. My findings demonstrate and focus on several political dimensions of the removal project, including funding, micro-political strategies, and the prioritizing of particular ecosystem functions and services in the post-removal landscape.

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 50-53). Also available on the World Wide Web.

Reformatted version of the author's thesis (M.A.)--University of California, Davis, 2003. / Includes bibliographical references (leaves 40-44). Also available in PDF via the Internet.

Thesis (M.S.)--Western Washington University, 2010. / Includes bibliographical references (leaves 56-63). Also issued online.

Dam removals are becoming increasingly common as dams reach their life expectancy and face costly upgrades associated with relicensing. Though removal is often viewed as a success in terms of ecological restoration, it also represents a major disturbance to an area. Previous research has shown that native species do not survive as well at these disturbed sites, and invasive species often dominate. This study examines the vegetation response in the drained reservoir area after the removal of Hemlock Dam on Trout Creek, a tributary to the Wind River in southern Washington. Transects were established and quadrats were sampled to determine the plant classifications and cover of vegetation and to examine possible correlations between environmental variables and the spatial distribution of plant classification groups. Sampling took place in the third and fourth years following dam removal, and the data was analyzed to determine significant changes and relationships. The results of this study showed that the site was dominated by a volunteer native forb Lotus purshianus (Spanish clover) and a planted native tree Alnus rubra (red alder). Most of the other species found were native volunteer forbs and grasses characteristic of early succession in this region. Both invasive species and planted species, with the exception of Alnus rubra, had low canopy covers. There was a significant increase in native plant canopy cover, as well as total canopy cover, from 2012 to 2013. There were also significant relationships between plant classification groups and environmental variables, including soil infiltration, elevation, and distance from stream. This study will help inform resource managers about the kinds of plants that will volunteer after dam removals and the possible success of re-vegetation projects.

Ecological conservation and restoration in the anthropocene must struggle with overlapping drivers of biodiversity and cultural loss; ruptures of the ecological environment mirror ruptures of human relationships with nature. And yet technology cannot remove humans from nature; technological and infrastructural reconfigurations of nature create new vulnerabilities and risks for humans and ecosystems alike. How can conservation and restoration science productively grapple with complex infrastructure systems and decision-making processes as biophysical and social drivers of ecosystem change? Using dam removals in the USA and in the Mid Columbia River region of the Pacific Northwest, this dissertation develops a conceptual framework for Social, Environmental, and Technological Systems (SETS), and applies it at three spatial and temporal scales to the practice of dam removal as a river restoration strategy. Drawing upon existing data sets, as well as biophysical, document, survey, and interview data this dissertation addresses how dam removals have functioned in the context of the social histories of river restoration programs, examines how these restoration programs must continue to renegotiate the human relationships with nature through the infrastructure systems that enable certain forms of existence while precluding others. Of particular interest is how restoration programs have increasingly functioned to deliver novel infrastructure solutions, while ignoring longer-term changes in ecological structure and function due to infrastructure development; in other words, the infrastructural work of restored ecosystems, and the infrastructural blind spots of restoration programs. How restoration planning considers, or does not consider, infrastructural blind spots, is indicative of not only the biophysical drivers of threatened and endangered species loss, but also the political dynamics of decision making at large, and the power-knowledge relationships constituting legitimate and relevant knowledge in the decision making space. In the Pacific Northwest, there appears to be a tipping point of social convention in centering treaty rights and obligations vis-a-vis ongoing processes of colonization and institutionalized scientific expertise. Ecological restoration will only be successful if it addresses both engineered infrastructures and social justice.

Following the removal of Marmot Dam on the Sandy River, Oregon, several Lidar flights were flown over the area of the former reservoir. The resultant sequential DEMs permitted calculation of reach-scale volumetric erosion and aggradation following dam removal. This allows for change detection across the entire affected reach of the former impoundment rather than just at several cross sections. In the first year there was a net loss of blank sediment in the dewatered reach. Subsequent flights show continued degradation of 145,649 m3 as well as aggradation of 6,232 m3. Sediment transport reached quasi-equilibrium in 2012 with a net change of 65 m3. In addition, this technique allows the extraction of cross-section information which shows that the channel continues to be actively migrating in some areas while also being constrained by bedrock features from past volcanism in some reaches. This study further shows the capability of lidar to measure rates of aggradation and degradation for an entire river system instead of reach specific extrapolations and that repeat lidar flights can more than adequately assess the changing nature of entire stream reaches more rapidly and more cost effectively than traditional field techniques. In addition: The utility of Lidar to do river management with repeat returns, having successive lidar acquisitions run on the watershed level will help us to gain insight into the correlation to precipitation events and geomorphological change in a given reach. Lidar can be used to assess the validity of channel evolution models. Sequential runs of lidar can be used to adjust the overall effectiveness of current CEM's and create new ones that consider reach specific geomorphology. Dam removal projects should incorporate initial lidar flights prior to removal and follow acquisitions based on known CEM's for the region and overall region-specific physiography. Sequential lidar should be used for hazard mitigation and geohazards analysis with an acquisition timeframe that is appropriate for the region's physiography, geology, geomorphology and the return interval of the hazard being monitored.

Emerging river policy has launched small dam removal as a viable option to meet the ecological and social demands for river restoration. As small dam removals gain precedence as a policy tool in river restoration projects there exists a glaring gap in the social considerations, in particular how small dam removals may affect existing community conditions. In order to determine the community impacts that may result, a case study of the Brownsville Dam Removal, in Brownsville Oregon was investigated to address two questions: 1) how has the Brownsville Dam removal affected the social and economic conditions of the community and 2) what indicators can be used to characterize and monitor the impacts. Twenty-nine semi-structured interviews were conducted with four community affiliations: 1) Canal Company members; 2) Calapooia Watershed Council members; 3) City Officials; and 4) community residents. A participatory social impact assessment (SIA) approach was used to validate existing and/or emergent impacts and indicators. The semi-structured interviews assisted in the development of a matrix of impacts and indicators specific to small dam removal. The local impacts and indicators were operationalized and measured. Findings suggest that the social and economic impacts when distributed across the community are minimal in this case of small dam removal. Because local data availability is limited, it was determined that the traditional social impact assessment framework can be vastly improved through the engagement of the community. This research further suggests that when collaboration is extended beyond a unidirectional flow of information (which is often the case in a traditional SIA), issues and concerns are open to deliberation in a non-threatening arena. The Calapooia Watershed Council served as the forum through which the residents of Brownsville were able to enhance their participation in decision making. This also contributed to a learning process that in the end furthered the community's understanding of the dynamic physical changes to the Calapooia River as well as their capacity to solve complex decisions. The case also demonstrated that collective learning is a reflective process of adjustment to the changing circumstances in which the community came to perceive, interpret, and act upon their interest. With a growing number of collaborative partnerships of watershed based management, distinguishable by their decentralized, participatory engagement of stakeholders, it may be likely that these place-based mechanisms will become the nexus to the successful coordination of small dam removal deliberation in the future. / Graduation date: 2010

Graduation date: 2006 / Dam removal is increasingly viewed as a river restoration tool because dams affect so many aspects of river hydrology, geomorphology, and ecology; but removal also has impacts. When a dam is removed, sediment accumulated over a dam’s lifetime may be transported downstream; and the timing, fate and consequences of this sediment remain some of the greatest unknowns associated with dam removal. In this thesis, I develop a conceptual model for erosion and deposition following removal of sediment-filled dams in mountain streams, and use field studies to document actual change. The data show that reservoir erosion in mountain rivers is likely to occur by knickpoint migration, with 85% of stored sediment being released during a single storm event in two field studies, at shear stresses less than that required for mobilization of the median surface particle size. Coarse sediment is predicted to deposit close to the dam with channel aggradation decreasing exponentially with increasing distance downstream, although some channel features are shown to have a greater propensity for aggradation than others. Field studies show that turbidity associated with dam removal and reservoir erosion may decrease hyporheic exchange, but gravel deposition (e.g., 470 m3 of gravel from Dinner Creek Dam) has the potential to more than offset that decrease, and increased hyporheic exchange is shown to reduce diurnal temperature change. Macroinvertebrate density and taxa richness did not respond to dam removal itself, but rather with time-lagged reservoir erosion. Following reservoir erosion, macroinvertebrate density recovered quickly, although longterm taxa community composition appears to be altered. On the Sandy River, field measurements of shear stress and patterns of sediment deposition following cold lahars were used as an analog to predict the fate of fine sediment, which is likely to deposit far from the dam. Results show that the Sandy River has little capacity for fine sediment storage in pools above RK 6.4 (~ 42 kilometers below Marmot Dam) at discharges associated with reservoir sediment releases. Taken as a whole, this paper illustrates a complex suite of process that may accompany removal of sediment-filled dams in mountain rivers.

The October 2007 removal of Marmot Dam, a 14.3-m-tall dam on the Sandy River in northwestern Oregon storing approximately 730,000 m3 of impounded sediment, provided an opportunity to study short- and long-term geomorphic effects of dam removal. Monitoring reservoir morphology during the two years following dam decommissioning yields a timeline of reservoir channel change. Comparison of a pre-dam survey in 1911 with post-removal surveys provides a basis from which to gage the Reservoir Reach evolution in the context of pre-dam conditions. Analyses of time-lapse photography, topographic surveys, and repeat LiDAR data sets provide detailed spatial and temporal documentation of a release of sediment from the reservoir following dam removal. The majority of morphologic changes to the reservoir largely took place during the first few days and weeks following removal. Channel incision and widening, along with gradient changes through the Reservoir Reach, exhibit diminishing changes with time. Channel incision rates of up to 13 m/hr and widening rates of up to 26 m/hr occurred within the first 24 hours following breaching of the coffer dam. Although channel position through the Reservoir Reach has remained relatively stable due to valley confinement, its width increased substantially. The channel reached an average width of 45 m within two weeks of breaching, but then erosion rates slowed and the channel width reached about 70 to 80 m after one and two years, respectively. Diminishing volumes of evacuated sediment were measured over time through quantitative analysis of survey datasets. About 15 percent of the initial impounded sediment was eroded from the Reservoir Reach within 60 hours of breaching; after one and two years, 50 and 58 percent was eroded, respectively. Grain-size analysis of terraces cut into reservoir fill following dam removal show that bed material coarsened over time at fixed elevations and vertically downward as the channel incised. Overall, these findings indicate valley morphology and local in-channel bedrock topography controlled the spatial distribution of sediment within the reservoir reach while variability in river discharge determined the timing of episodic sediment release. Changes within the Reservoir Reach shortly after dam removal and subsequent evolution over the two years following removal are likely attributable to 1) the timing and intensity of flow events, 2) the longitudinal and stratigraphic spatial variations in deposit grain-size distributions initially and over time, and 3) the pre-dam topography and existing valley morphology.