Geotechnical engineering and geology faculty at Drexel and Villanova Universities and a graduate teaching assistant collaborated with an environmental hydrogeologist from a local civil engineering firm to develop a field trip for their undergraduate engineering geology courses. At Villanova, Geology for Engineers is required for all civil and environmental engineering students. Similarly, at Drexel, Geologic Principles for Infrastructure & Environmental Engineering is a required course for all civil, architectural and environmental engineering students. The learning goal of both courses is to have students understand how basic topics in geology and geomorphology apply to civil and environmental engineering practice. The field trip focuses on the core elements of the courses: the importance of rock type on engineering properties, the effects of plate tectonics and weathering on rocks, and the interaction of human activity with the lithosphere and hydrosphere. The team selected Wissahickon Valley Park as the location for the field trip because it provides a dynamic stream ecosystem within a geologically diverse setting that has been highly impacted by urban development of the surrounding City of Philadelphia. The engineering aspects bring novelty into an established practice of classical geology field trips. In addition to examining outcrops and evidence of geologic processes, the students were required to critically identify engineering issues associated with the infrastructure in the valley, storm water management, and the impact of development on the stream valley. From anonymous surveys disseminated after the first offering of the field trip, students indicated the trip had enriched their learning experience, improved their ability to apply basic geology knowledge in a real-world context, and increased their interest in how rock, soil, water, and climate play roles in infrastructure engineering. Without exception, the students agreed that the field trip should be offered again. This presentation will describe the development of the collaboration between the educators and practitioners, the resulting field trip and materials that have been adopted at both universities. We will also update the surveys’ results from two more trips of the fall of 2018.

Rain gardens are green stormwater infrastructure that are designed to leverage natural processes to mitigate the impacts of urban stormwater through capturing, infiltrating, and filtering run off. Overtime these systems have the potential to buildup fines and nutrients, impacting their sustainable function. A rain garden’s performance depends on its ability to infiltrate runoff which can be reduced by clogging. Another concern is the potential transport of contaminants from rain gardens to groundwater through deep drainage. This study analyses the spatial and temporal distribution of fines and nutrients in three rain gardens through comprehensive field tests, laboratory testing, and computation analysis. Geomorphic studies were performed by integrating the digital elevation models, derived from Lidar surveys, with the FastMech solver within International River Interface Cooperative (iRIC) software, to model shear stress distribution and sediment transport relative to spatial observations of soil texture and nutrient concentrations within the rain garden. The soil properties were also used in creating models of water infiltration and nutrient sorption using Hydrus 1D. Results show that shear stresses in localized sections of each rain garden can be correlated with fines and nutrient distributions, allowing for prioritizing locations for maintenance. To conclude, LiDAR scans, flow and shear stress models, infiltration and nutrient transport models, field and laboratory soil tests can help us understand the surface dynamics and soil attributes, and gradually gain insight into the GSI performance with time.