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Abstract In meandering rivers, interactions between flow, sediment transport, and bed topography affect diverse processes, including bedform development and channel migration. Predicting how these interactions affect the spatial patterns and magnitudes of bed deformation in meandering rivers is essential for various river engineering and geoscience problems. Computational fluid dynamics simulations can predict river morphodynamics at fine temporal and spatial scales but have traditionally been challenged by the large scale of natural rivers. We conducted coupled large‐eddy simulation and bed morphodynamics simulations to create a unique database of hydro‐morphodynamic data sets for 42 meandering rivers with a variety of planform shapes and large‐scale geometrical features that mimic natural meanders. For each simulated river, the database includes (a) bed morphology, (b) three‐dimensional mean velocity field, and (c) bed shear stress distribution under bankfull flow conditions. The calculated morphodynamics results at dynamic equilibrium revealed the formation of scour and deposition patterns near the outer and inner banks, respectively, while the location of point bars and scour regions around the apexes of the meander bends is found to vary as a function of the radius of curvature of the bends to the width ratio. A new mechanism is proposed that explains this seemingly paradoxical finding. The high‐fidelity simulation results generated in this work provide researchers and scientists with a rich numerical database for morphodynamics and bed shear stress distributions in large‐scale meandering rivers to enable systematic investigation of the underlying phenomena and support a range of river engineering applications.
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This content will become publicly available on May 15, 2026
Exploring Variations in High-Resolution Downstream Hydraulic Geometry of the Logan River
Rivers are dynamic systems that change shape due to natural events like floods, landslides, and wildfires, as well as human-made structures like bridges. These changes create unique and complex river patterns. However, measuring these changes accurately is challenging because traditional field surveys are time-consuming and often focus on easily accessible areas, which may not represent the whole river. Thanks to new high-resolution mapping technology and detailed river flow records, we can now see these changes in greater detail than ever before. In this study, we focused on the Logan River, which flows through a canyon with a mix of rocky and sediment-filled areas. Using advanced mapping tools, we measured the river's width along a 45 km stretch and checked these measurements against field surveys to ensure accuracy. This approach allows us to identify sections of the river that show consistent patterns and those that deviate due to factors like incoming streams or human impacts like roads. Understanding these variations helps us to better plan for infrastructure projects, river restoration, and managing natural hazards. Our method provides a new way to understand how changes in the environment affect rivers, which can lead to smarter, more resilient design and planning.
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- Award ID(s):
- 2220505
- PAR ID:
- 10610205
- Publisher / Repository:
- USU Digital Commons
- Date Published:
- Format(s):
- Medium: X
- Institution:
- Utah State University
- Sponsoring Org:
- National Science Foundation
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