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wetland impacts projected. One or two private land parcels would be involved in the construction; special stipulations are being mutually negotiated to protect this land and its uses during construction and to restore any damages following construction. There would be no change in land use or ownership. The primary uses of irrigation water diversion and residential use would continue. River Flows. Water Rights, and Water Uses The Colorado River in the general area is the key source for irrigation water in the Grand Valley. Mean monthly streamflows upstream of the GVIC Canal are summarized in Table B-1 in Appendix B. The peak runoff occurs in May and June with mean monthly streamflows of 7,118 cfs and 10,564 cfs, respectively. The flows subside in July with a mean monthly streamflow of 4,693 cfs. Mean monthly streamflows are lower in the fall, around 1,000 cfs. GVIC owns 640 cfs in water rights that are senior to most users on the river. This water continues to be used for agricultural purposes although, increasingly, it is used for residential irrigation. Water from another irrigation system, the Orchard Mesa system, is diverted further upstream. Some of this water is dropped through a hydropower system that then enters the river a short distance downstream from the GVIC Diversion. A system has been developed where some of the Orchard Mesa water discharge can be "checked" back upstream to a point above the GVIC Diversion, and thus be used for GVIC purposes. Recent agreements have been reached on how this "check" can be operated to both protect water users and enhance the river habitat for endangered fishes. Under the No Action alternative, significant changes are not anticipated on the water systems or operations under the "check" agreements. The addition of the passage would enhance the ability of the Recovery Program to recover the fish and thus, offset impact of water development and use on endangered species. This will have a positive influence on permitting of future water activities. Providing passage at the GVIC Diversion Dam would have no effect on GVIC's ability to fully use their water rights. Additional operation and maintenance work would be required, particularly if screening of the canal inlet is included in the future; however, the costs and responsibility for these activities would lie with the Recovery Program and/or the Service. In certain low flow conditions, streamflows could be augmented to allow upstream passage of the endangered fish during the July to October period. Reclamation has storage water in Ruedi Reservoir that is committed to the Recovery Program which can be used to augment the streamflows. This augmentation would provide some enhancement of river habitat conditions as well as assisting in fish passage. Agreements on operation of the Orchard Mesa check would not 16