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Hyporheic hydrodynamics are a control on stream ecosystems, yet we lack a thorough understanding of catchment controls on these flow paths, including valley constraint and hydraulic gradients in the valley bottom. We performed four whole-stream solute tracer injections under steady state flow conditions at the H. J. Andrews Experimental Forest (Oregon, United States) and collected electrical resistivity (ER) imaging to directly quantify the 2-D spatial extent of hyporheic exchange through seasonal base flow recession. ER images provide spatially distributed information that is unavailable for stream solute transport modeling studies from monitoring wells alone. The lateral and vertical extent of the hyporheic zone was quantified using both ER images and spatial moment analysis. Results oppose the common conceptual model of hyporheic ''compression'' by increased lateral hydraulic gradients toward the stream. We found that the extent of the hyporheic zone increased with decreasing vertical gradients away from the stream, in contrast to expectations from conceptual models. Increasing hyporheic extent was observed with both increasing and decreasing down-valley (i.e., parallel to the valley gradient) and cross-valley (i.e., from the hillslope to the stream, perpendicular to the valley gradient) hydraulic gradients. We conclude that neither cross-valley nor down-valley hydraulic gradients are sufficient predictors of hyporheic exchange flux nor flow path network extent. Increased knowledge of the controls on hyporheic exchange, the temporal dynamics of exchange flow paths, and their the spatial distribution is the first step toward predicting hyporheic exchange at the scale of individual flow paths. Future studies need to more carefully consider interactions between spatiotemporally dynamic hydraulic gradients and subsurface architecture as controls on hyporheic exchange.

This research presents an integration of remote sensing and GIS for determining the runoff coefficient (C) recommended by American Society of Civil Engineers and Water Pollution Control Federation in 1969. The C is a runoff index used as an input parameter in the most commonly used procedure-the rational method for runoff calculation in small urban watersheds for storm drainage design and analysis. The objective of this study was to evaluate 8 and 16 bit QuickBird (QB) NDVI satellite imagery using an unsupervised classification and the ISODATA algorithm to map impervious area and open space used for the determination of C in GIS spatial modeling. The research hypothesis was that mapping impervious area and open space using high spatial resolution NDVI satellite imagery, generated using the ISODATA algorithm, was an efficient and effective information extraction approach for accurately determining the C value. The 2004 data were provided by the City of Sioux Falls, South Dakota. The overall classification accuracies of the six QB NDVI thematic maps produced were similar, about 92%. In order to assess the utility of high spatial resolution satellite imagery and to validate the composite runoff index geographic model developed by Thanapura in 2005 and 2006, the C values were calculated in GIS spatial modeling and compared to the industry standard C. Finally, the hypothesis was accepted that finer resolution image and mapping approach used in this study allowed for better discrimination of land cover and thus a more accurate C estimation.

Program success at tribal colleges and mainstream universities is often identified solely with matriculation and graduation rates. However, particularly for new STEM programs, capacity building is another key measure of success. In this paper, three of the co-authors, who are faculty members at a tribal college and participants in a multi-year collaborative pre-engineering education initiative between a tribal college and two Regental universities, provide their perspectives on capacity building in summer research activities within the alliance. The three each wrote essays reflecting on capacity building guided by pre-determined questions written by another co-author. Through qualitative analysis, we present common themes, divergent opinions, and quotations extracted from the essays from their unique perspective as faculty at a tribal college. We emphasize impacts among the partnering schools, faculty, students, and communities where the summer research activities took place. Three common themes dominated the essays including the importance of (1) building trust within the reservation community, (2) employing experiential and aspects of project-based service-learning approaches, and (3) encouraging tribal college and university leadership in the determination of research and educational foci in institutional collaborations such as ours.

In an effort to prepare more Native American engineers, counting the numbers who complete the educational task is important. More often overlooked, however, is that capacity building is another key measure of success, since reaching critical mass to obtain the numbers may take considerable time. In this paper, the co-authors are both the researchers and the research subjects. We are four engineers and/or scientists with advanced degrees with key roles in a multiyear collaborative pre-engineering education initiative between a tribally controlled college and two mainline universities. From our perspectives at one of those two mainline universities, we each wrote an essay reflecting on pre-determined questions. We briefly present our qualifications and then assess capacity building related to the summer camp experiential learning aspect of the initiative. We qualitatively analyze the essays and present persistent themes, along with consensus and divergent opinions. Four common themes dominated the essays including the importance of: (1) using experiential learning pedagogy, (2) building lasting relationships and networking, (3) including cross-disciplinary connectivity, and (4) taking advantage of positive but unintended consequences. We provide a recommended bibliography for faculty, staff, graduate students, and undergraduate student interns to provide a shared base of knowledge to improve collaborative cohesion.