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("I"; ,'V. ~ - FISH AND WILDLIFE SERVICE REPORT C'.:; "",-.." channel is approximately 150 feet wide and 3 feet deep in the project area with an estimated gradient of 64 feet per mile. The stream banks are covered with cottonwoods, willows, and brush. The stream bottom is composed of sand, rubble,. and boulders, with few pools. The Green River is not considered a heavy sediment -bearing stream near the diversion dam site, but it picks up considerable silt through the project area and some pollution below Green River, Wyoming. 12. The average annual discharge for the Green River at the Seedskadee diversion site during the period 1931 to 1947, inclusive, was 944,900 acre- feet. Water shortages would have occurred during the following periods: July through September .of 1931; August of 1933, June through September of 1934; and July through September of 1940. The maximum discharge observed at Green River, Wyoming, was 22,200 second-feet on June 19, 1918; the mini- mum observed was 160 second-feet on November 17, 1898. The flows with- and without-the-project are shown in Table 1. 13. Vegetation. -The tops of the Uinta Mountains to the south of the proj- ect are above timberline, with the characteristic dwarf willow, sedges, and other alpine scrub plants. The slopes are covered with dense forests of spruce, firs, and pines, with aspen at the lower edge. Below the tim- ber belt are extensive areas of sagebrush and shadscale with an understory of grasses and small annuals. Most of the project area lies in a desert shrub community where the vegetation on the low rolling hills, consists principally of sagebrush, shadscale, grasses, and small desert shrubs. 14. The anticipated crop distribution after settlement of the project lands is as follows: permanent pasture, 33 per cent or 20,000 acres; alf- alfa and rotation pasture, 46 per cent or 28,000 acres; and small grains, 21 per cent or 12,720 acres. 15. Engineering features of the project. - The Seedskadee diversion dam would consist of a low concrete ogee overflow section 400 feet in length and an earth embankment 1000 feet long. The overall height of the dam would be 19 feet with the ogee crest 9 feet above stream bed. The head- works to the canal would have a gate capacity of 1,350 second-feet with a sluiceway discharging onto the downstream apron of the dam. 16. A combined fish-screen structure and wasteway would be provided. The wasteway would precede the fish screens and would divert all or part of the flows in the canal back to the Green River. The fish screens, located in the canal about 3,000 feet be low the headworks, would consist of six separate units of rotary screens 20 feet wide by 9 feet in diameter. 17. The diversion canal, predominantly an earth section, would convey water 19 miles to the head of the project lands where it would be diverted into the Green River siphon and the West Side Canal, 3