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electrical pumping at the Forebay, Bridges Switch, and 271,-B'I; Road Pump Stations. Present facilities are not adequate to completely make up the loss of irrigation water and cost of pumping and O&M are very significant. The loss of power generation reduces revenues that are committed to loan repayments pursuant to contracts among the United States, Grand Valley Water Users' Association and Orchard Mesa Irrigation District. Operation of the "check" is not a simple matter. When the river is on "call" it is very difficult for the State Engineer to keep the distribution and delivery of water in balance. This,is particularly true if prompt and effective action is not taken to administer the river and implement releases from Green Mountain Reservoir. Since it requires about 62 hours for the water to reach the Grand Valley, more often than not, by the time the re- placement water has arrived the river had dropped even further. This results in shortages to the Grand Valley Project to the benefit of Junior Appropriators. The proper way to operate the "call" would be to shut off junior rights until replacement water from Green Mountain Reservoir has arrived at their diversion points. Often the "check" has to be implemented prematurely to avoid serious water shortages to the Grand Valley Project. Any idea that the "check" has to be in operation before the "call" is placed on the river is erroneous. Operation and maintenance of the "check" is expensive. Present physical ar- rangement of the "check" and By-pass Channel allows flood water of the Colorado River to flow back into the By-pass Channel and fill it with sediment. This requires considerable dredging and maintenance work before the channel can be used to check the water back. This is especially true since the channel is not used every year. The channel will not presently convey the full 640.28 c.f.s. right of the Grand Valley Irrigation Company without considerable preparatory work. To function properly, the By-pass Channel should be concrete lined, with a measuring facility and radial gates constructed at each end of the By-pass Channel. The "check" structure itself is approximately 60 years old. Major modifications were made in about 1956 to install radial gates to replace flash uUd,'ds. CUlIsiderdble r'ehdbil itation of the structure is required as shown on the attached photos. Options The present arrangement of diverting and checking Grand Valley Irrigation Co. water for power and pumping purposes is carried out at the discretion and for the specific benefit of the Grand Valley Project. However, if satisfactory arrangements were made to mitigate all impacts associated with the checking, then Grand Valley Project power and pumping water could be checked back which would supplement releases from Green Mountain Reservoir for the benefit of water rights junior to the Grand Valley Project and Grand Valley Irrigation Company. Orchard Mesa Irrigation District is unwilling to operate and maintain the check structure and related facilities at it's expense together with loss of power revenue of the Grand Valley Power Plant and pumping efficiency of the Palisade PUlllpill'l Plolnt f(lI' the bp.nl'fit of Junior Appropriators. -2-