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Show " The bed material is a problem which will persist., The channel will migrate and Hayes Reservoir will gradually lose capacity as the material is flushed from the channel. " If a new flow regime is to be initiated by the Central Utah Project, it should be based on the physical properties of the channel. Under current conditions the most desirable flow rate would be approximately 130 c. foS., the natural maximum mean monthly discharge. At this level, only 2 percent of the available bedload material can be transported. The stream channel will be stable and the habitat improved0 Artificial flows should not vary more than 25 percent of the mean if stability of the channel is to be realized. QUESTIONS " A. Roads " The existing system of Forest roads has and will continue to have a serious impact on the hydrologic functioning of watersheds. The increased runoff resulting from construction of many miles of Forest roads seriously damages forest watersheds particularly from erosion. Roads have been a major contributor to the increased flow of sediment resulting from on- the- ground development and use of the forests. As much as 90 percent of the increased sediment caused by use of the forests may be attributed either directly or indirectly to construction and use of roads. Keeping in mind the impact of roads on the National Forest, it is important that the following questions be answered. Without the answers it is impossible to accurately evaluate the environmental impacts of the Central Utah Project. " 1. How many miles of road are to be constructed in connection with the Central Utah Project? n2„ How many surface acres will the road prism occupy ? " 3. What will this mean in sediment production ( tons/ year) during construction, during curing ( or the first 3 years after construction) , and the long- term life of the road? 259 |