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OJJ2H Increased stage causing bank storage due to a reservoir run may In cer- tain places cause increased transpiration In plants. No data are available to quantify this "loss" caused by a temporary rise In stage of a river. 43 For calculatIon purposes bank storage was divided Into three major cate- gories: one was the wedge storage along.the effluent reaches of the stream; two, a volume of storage due to a general rise In ground water, generally occurring In the reaches where there are oxbows and river bends In a wide anuV:la:1 valley; and third, loss of water due. to an influent condition. It was assumed that 3~!o of the wedge storage would return to the stream quickly enough after sh~t off,to be diverted by the receiving ditch. Twenty per cent of the general water table rise was assumed to return for diverslon.* And It was assumed that nOne of the "Influent" water was divertable. Several calculations were made using the above assumptions on different reservoir release rates for different rIver conditions. The calculations of per cent loss of total reservoir release due to bank storage ranged from ~!o to ~!o depending on the stage of the rIver and size of the release. Bank storage losses that are chargeable to a reservoir run are depend- ent on many dIfferent factors. Until a very detal led study can be performed, It Is our opinion that a bank storage charge for reservoir releases'from Twin lakes to the Colorado Canal should be made In accordance with the following formula. Chargeable loss in % of total release = 6 - 0.004 Qcc or 2% whichever Is greater where Qcc Is the flow at Canon City before the release. CHARGEABLE lOSSES For administrative purposes, charg~able losses, with present knowledge, can be put Into three major categories: evaporation, unauthorized diversions, and bank storage. Calculation and/or estimation of each of these has been presented above. Table V-I entitled "Transit losses to be Charged to Reser- voir Run on the Arkansas River" has been presented to aid In computing the losses to be charged to a reservoir run. Tables V-Ia and V-Ib are examples of how transit losses along the upper Arkansas River can be computed. If significant conflicting evidence Is developed which demonstrates that transit losses are actually different than those presented In this report, either higher or lower, It Is believed that the higher transIt losses should be given more weight In the final analyses to protect the ownerS of vested water rights to the natural flow. The proof of lower tr.nslt losses, from an engineering point of vIew, should be made by those using the river as a carrier. Furthermore, It should be noted that evaporatIon losses used here are "Incremental" losses. If the full evaporation of the river were to be pro- rated between the natural flow and t~e transported water, then the evapor- ation loss would be substantially more, depending upoo the reservoir run. *Backup data provided separately.