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I I I Under the current operations for John Martin Reservoir, there is no way to exchange this accretion portion of Keesee Ditch winter diversions upstream to storage in the dam whenever the gates are closed. At the same time, it is impractical to open the gates to make minor releases to satisfy Keesee Ditch winter return flow obligations except in combination with other releases. And finally, if Keesee Ditch return flows were made to the river, historical diversion patterns make it unlikely that any downstream ditches would make use of the water during the winter months. I I I I I Historical operations of the ditch indicate that average winter diversions (November through March) were exceeded by average winter return flows for a net river accretion of about 114 acre-feet. Since it is impractical to operate actual diversions and return flow releases under the John Martin Reservoir operating plan during these months, it is proposed that a winter return flow obligation be calculated based on this historical winter season accretion. The amount of the winter return flow obligation would be based on the preceeding summer season (April through October) diversions. Using the historical averages (Table Ill, this corresponds to a winter return flow obligation equal to 2.58 percent of summer season diversions. I I I I I I I I I I I In accordance with this simplified relationship, the Keesee Ditch would"\. not utilize its priority to divert from river flow during the months of November through March. Since it is impractical to release the winter return flow obligation during the winter months, it is proposed to release 2.58 percent of the previous year's diversions directly to the river as part of normal summer reservoir releases. Although the timing of these returns are not patterned as they have been historically, it is anticipated that downstream water users will enjoy greater benefit of a summertime release of this water. -10-