Modeling a plunge pool in HEC-RAS
Modeling a plunge pool in HEC-RAS
(OP)
I am modeling a relatively steep channel(3% slope). Channel bottom is shale with quite a few plunge pools. I'm wondering is anyone knows of a reference for how to model the plunge pools in HEC-RAS?





RE: Modeling a plunge pool in HEC-RAS
RE: Modeling a plunge pool in HEC-RAS
RE: Modeling a plunge pool in HEC-RAS
Jarrett's equation is a good spot to start for Manning's "n" on steep riffle/step-pool reaches with low flows. During higher flows, the step-pools tend to have less influence and Manning's reverts back to that obtained with traditional methods considering bed material and vegetation.
Jarrett's:
n = 0.32 x [slope]^0.38 x [hydraulic radius]^(-0.16)
Jarrett, Robert. 1984. Hydraulics of high-gradient streams. Journal of Hydraulic Engineering. 110(11): 1519-1539.