Abstract
Regime channels are important for stable canal design and to determine river response to environmental changes, e.g., due to the construction of a dam, land use change, and climate shifts. A plethora of methods is available describing the hydraulic geometry of alluvial rivers in the regime. However, comparison of these methods using the same set of data seems lacking. In this study, we evaluate and compare four different extremal hypothesis-based regime methods, namely minimization of Froude number (MFN), maximum entropy and minimum energy dissipation rate (ME and MEDR), maximum flow efficiency (MFE), and Millar’s method, by dividing regime channel data into sand and gravel beds. The results show that for sand bed channels MFN gives a very high accuracy of prediction for regime channel width and depth. For gravel bed channels we find that MFN and ‘ME and MEDR’ give a very high accuracy of prediction for width and depth. Therefore the notion that extremal hypotheses which do not contain bank stability criteria are inappropriate for use is shown false as both MFN and ‘ME and MEDR’ lack bank stability criteria. Also, we find that bank vegetation has significant influence in the prediction of hydraulic geometry by MFN and ‘ME and MEDR’.
Highlights
An alluvial channel, either artificial or natural, persists to deform its boundary by itself while transporting water and sediments
Regime channels have been used for stable canal design [2,3] and to determine river response to environmental changes like climate shifts, construction of dams, land use changes, and river training [4,5,6,7]
A plethora of methods is available describing the hydraulic geometry of alluvial rivers in the regime
Summary
Either artificial or natural, persists to deform its boundary by itself while transporting water and sediments. If water and sediment rate remain constant, the deformation ceases after a certain period to achieve regime state or dynamic equilibrium or quasi-equilibrium [1]. The hydraulic geometry characteristics of the channel remain invariant with time, having many economic and ecological benefits. Regime channels have been used for stable canal design [2,3] and to determine river response to environmental changes like climate shifts, construction of dams, land use changes, and river training [4,5,6,7]. A plethora of methods is available describing the hydraulic geometry of alluvial rivers in the regime. American Society of Civil Engineers (ASCE) Task Committee [8] has grouped regime methods into empirical (regime theory and power law), rational, or mechanistic and extremal hypotheses
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
