To Plot snyder’s unit hydrograph we need value of basin lag (tpr), time base(tb) , width of hydrograph at 50% discharge(W50) , width of hydrograph at 75% discharge(W75) The peak time is distance from centroid of effective rainfall to peak of the discharge. where, tp = Peaking time in standard condition tpr = Basin lag in general condition C1=0.75 Ct=Watershed factor where, qp is peak discharge per unit catchment area Cp=Watershed factor C2=2.75 C3=5.56 The width of hydrograph at 50% of peak discharge […]