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Average annual peak flow in Savery Creek will be delayed by 3 days on average and 25 days maximum and reduced by 165 cfs (4.7 m3/s). Water diverted for irrigation will be lost because of evapotranspiration. This will result in a maximum reduction in average monthly discharge of 10% in April and a maximum increase of 23% in October in the Little Snake River at the "near Lily" gage. Average annual depletion in the Little Snake River will be 10,836 af. Salts in the Little Snake River are predicted to increase about 25% during base flow (Burns and McDonnell 1999). Sediment Yield The Little Snake River sediment load constitutes approximately 77% of the Yampa River sediment load in Deerlodge Park (O'Brien 1987). Roughly 60% of the total sediment load in the Yampa River is derived from the Little Snake River between Dixon and Lily (Andrews 1978). Andrews (1978) arrived at this conclusion by examining the difference in the computed average annual sediment loads based on the available data at the Dixon and Lily gages. This portion of the basin is underlain by relatively young, high erosion sedimentary formations. Very little information is available to quantify the sediment yield of the various tributaries of the Little Snake River basin. The four major tributaries draining this area were ranked by RCI (1991) in terms of sediment contribution as follows: 1) Sand Wash, 2) Muddy Creek, 3) Sand Creek, and 4) Powder Wash. Sand Wash and Muddy Creek were given relatively equal rankings. As was previously discussed, the poorly cemented sandstones, siltstones and mudstones combined with the effective rainfall and sparse vegetation generate a high sediment yield from these tributary basins. Most of the available data base for determining sediment yield in the Little Snake River basin was collected at the Lily Gage between 1959 and 1964 when suspended load measurements were made on a daily basis (Table 1). This core 19