CIV E 530 - OPEN-CHANNEL HYDRAULICS FALL 2012 LAB No. 1:  OPEN CHANNELS An irrigation channel operating on a hilly slope at Vedernikov number V = 1 has a potential to develop roll waves. To eliminate this possibility, a new channel has been proposed with a slightly different alignment, operating at Vedernikov number V = 0.75. The channels are concrete lined and Chezy friction is applicable. At the design depth, the ratio of top width to wetted perimeter is nearly the same for both channels. Assume that the exponent of the rating β is the same for both channels. The bottom slope in the old channel is So = 0.025. Calculate the bottom slope in the new channel. The minimum practical slope permitted by the terrain is S = 0.02. Determine whether a series of drops will be necessary in the new channel.