Numerical Modeling of Nature-Based Flow Regulation in Floodplain Canals during High Discharge Events

Abstract:

This study investigates riparian vegetation as a mitigation measure for overflow and bank erosion in the Jumman Shah Canal, Pakistan, using Computational Fluid Dynamics (CFD) with the Volume of Fluid (VOF) method for free-surface flow simulation. Three cases were modeled: bare floodplain (existing condition), submerged vegetation, and emergent vegetation. Vegetation was represented as uniformly spaced cylinders to maintain consistent porosity, with a 1:100 geometric scale replicating prototype peak-flow conditions. Field velocity measurements validated the model, showing strong agreement with simulations. Results showed submerged vegetation induced moderate backwater effects and broader low-velocity zones, while emergent vegetation produced greater upstream water level rise, higher momentum attenuation, and a delayed, confined high-velocity core. Both vegetation types increased hydraulic resistance and improved flow uniformity compared to the bare channel, with emergent vegetation offering the highest flood energy dissipation. The findings advocate vegetation-based stabilization as a sustainable, cost-effective approach for enhancing canal resilience.

• Periodical: Construction Technologies and Architecture (Volume 23)
• Pages: 165-170
• DOI: https://doi.org/10.4028/p-RCjz2Q
• Online since: May 2026
• Authors: Syed Muhammad Ahmad Bukhari*, Naveed Anjum, Muhammad Asghar
• Keywords: Bank Overflow, CFD, Emergent Vegetation, Floodplain Stabilization, Submerged Vegetation, Wahi Jumman Shah Canal

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