Coupled sand and clay motion, bed morphodynamics, and porewater exchange

BSF Application number: 2017603 Coupled sand and clay motion, bed morphodynamics, and porewater exchange Aaron Packman1, Rina Schumer2, and Shai Arnon 3

1 Department of Civil and Environmental Engineering, Northwestern University, USA

2 Division of Hydrologic Sciences, Desert Research Institute, USA

3 Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel

Abstract- lay terms Clay-sand mixtures occur ubiquitously in freshwater and marine environments. The transport and mixing of these sediments control diverse fundamental system attributes including bottom topography, sediment hydrogeological properties, sediment stability, and ecological habitat conditions. However, little is known on how coupled clay-sand-water dynamics control sediment movement in streams and coastal regions because traditionally these processes were evaluated separately for sand and clay. This project aims to measure how coupled clay-sand-water interacting with each other under various chemical and physical conditions, and develop mathematical models that will enable to predict these processes. Experiments and theoretical analysis will be performed collaboratively between the U.S. and Israeli institutions. Project results will directly inform the geomorphology, hydrology, and oceanography research communities on potential long-term land/seascape changes. Primary broader impacts are: 1. Acquisition and dissemination of high-resolution datasets for validation of earth-surface & marine morphological models. 2. Development of transferrable theory for assessing coupled sediment transport and stability in rivers and the continental shelf. 3. Project results directly inform assessment of ecological impacts and design of restoration strategies for stream siltation and remediation of contaminated sediment sites. 4. Extensive value for K-12 education and research capacity-building. Translation of research methods and data products for education will engage several hundred junior-high and high-school students per year. Cross-training of graduate students and postdocs between the U.S. & Israel will provide essential international research experience and yield a cohort of junior researchers well-prepared to advance broad understanding of sediment-water dynamics across freshwater and marine systems.