Channel routing is the calculation of the hydraulic parameters of a floodwave as it moves through a channel. The overall movement is typically described with the concepts of celerity and attenuation. Floodwave celerity is the speed at which the floodwave moves down the channel and is primarily a function of the channel slope. The attenuation of a floodwave is the subsidence or flattening of the wave as it moves down the channel. Floodwave attenuation is directly related to the amount of inchannel or riparian storage available.