ROVER: Introducing A Unified Model To Estimate The Hydraulic Resistance Of Vegetation

The specification of flow resistance is central to both simple and sophisticated hydraulic analyses. Yet it remains encumbered with the greatest level of uncertainty of all hydraulic parameters; despite over a century of field and flume experimentation. The selection of resistance coefficients for natural rivers remains more an empirical art than a matter of implementing robust scientifically verified procedures (Yen, 1991). The complexity and variety of boundary conditions are the principal impediments to developing reliable resistance estimation tools. A range of boundary features contribute to flow resistance and, of these, vegetation is the most potent (Cowan, 1956; Watson, 1987) but the least amenable to theoretical analysis. Plant structures are challenging to describe numerically because of their myriad of shapes, structures, and the mosaic of their distributions along rivers.