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## Conveyance calculation

 Hi everybody. I'm new to the forum and don't know if this has been answered before. I'm using Hec-Ras to solve one of the examples, in particular Critical Creek (Critcrek.prj). I can't understand how is conveyance calculated for the left overbank. While it is calculated correctly for the main channel and right overbanks as K=1.486/n*A*R^(2/3), this doesn't hold for the left overbank. This continues for all 12 sections but the maximum error is for section 2 (6.26%). Here are the numbers for the second section as copied from the table: Area left             2086.7 Area channel         236.92 Area right                0 W.Perim left          641.54 W.Perim channel      48.61 W.Perim right            0 H.Radius left             3.25264  OK H.Radius channel       4.8738    OK H.Radius right           0.66199   OK Conveyance left        72617   (1.486/0.1*2086.7*3.25264^(2/3)=68072.2)                Differece =  4544.8   WHY ????Conveyance channel  25300    (1.486/0.04*236.92*4.8738^(2/3)=25301)  OK Conveyance right            0     (1.486/0.1*0*0^(2/3)=0) OK