props = rd.FlowProportions(dem, method='Freeman', exponent=1.1)

#30% of the flow moving along any route is absorbed
props[props>0] *= 0.7
accum = rd.FlowAccumFromProps(props=props)

rd.rdShow(accum, ignore_colours=[0], figsize=(8,5.5), axes=False, cmap='jet', zxmin=450, zxmax=550, zymin=550, zymax=450)