Quantification of transit losses, and its effects on surface-water resources, Arkansas River basin, Colorado

Colorado Water Law enables downstream water users to use natural river channels to convey water from upstream storage reservoirs to downstream canals, provided an equitable charge is made for transit loss. Charging a variable transit-loss rate for delivery of winter water stored in Pueblo Reservoir has resulted in better management of the basin's surface-water resources. Not only are more accurate volumes of stored water delivered to each irrigator, but use of the natural channel for conveyance of these waters now has minimal effect on users of direct-flow water rights. A better understanding of specific sources of transit loss also has allowed water users to manage the timing and rate of their reservoir releases to optimize beneficial use of their stored water.