PARTICIPANTS
Gregory B. Pasternack and Joshua R. Wyrick

OVERVIEW
The river step is an important driver for geomorphic evolution in bedrock rivers. Inherent to a river step is the associated hydraulic jump, whose regime is a primary control on channel erosion. Additionally, the hydraulic jump regime is controlled by several independent and dependent variables. A new conceptual model linking these variables to step dynamics and bed incision has been developed and quantified. Previously, the model delineated jump regimes and quantified energy dissipation accounting for jump submergence and discharge in a uniform channel. In this next stage, the equations have been further generalized to account for the critical role of channel geometry upstream and downstream of a step. The jump regime and energy dissipation tend to be more sensitive to channel configuration as discharge increases and/or step height decreases. For a given discharge and step morphology, an increase in the rate of downstream widening leads to an increasingly emergent jump.

The results from this project are currently under peer review.

Comments and feedback to gpast@ucdavis.edu