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The Dirty Devil River enters Lake Powell near Hite and adds a mean annual 99 cfs flow. The river is named for the heavy amount of suspended sediment attained in its journey through highly erodible soils. Peak flows generally occur in March and low flows are experienced in July. Daily flows range between 0-14,000 cfs. The input is quite steady within the range of 50- 250 cfs. The Escalante River has not been controlled by dams but some water is used seasonally for irrigation needs. Average inflow was 10 cfs for water years 1973-1994, with mean annual variation between 1.5 to 30.7 cfs. Mean daily flows ranged between 0.7 and 270 cfs, with peak flows in March and low flows in July. The Paria River enters Glen Canyon NRA at Lees Ferry, downstream from Glen Canyon Dam and below the 15 mile trophy trout tailwater. Average flow is 2 cfs of silt laden water that joins with the clear, cold Colorado River tailwater at Lees Ferry and adds the first suspended sediment load back into the system below the dam. The completion of Glen Canyon Dam in 1963 formed a new reservoir that eventually backed up some 186 miles behind Glen Canyon Dam. Within Glen Canyon NRA, water resources are grouped into the following habitat types: a. Flowing rivers: River reaches exhibiting current offer habitat and conditions most similar to the river system prior to control by impoundments. The flood-prone, often turbulent, turbid Colorado River above Glen Canyon NRA still offers river habitat somewhat resembling that found prior to impoundment and development of the Colorado River. Native species may have some preference or adaptations to survive in flowing rivers, however, even the flowing portion of controlled rivers now exhibit alterations in many conditions such as: temperature, hydrography, and sediment and debris transport compared with historical pre-dam conditions. Flowing river reaches on the Colorado, San Juan, Dirty Devil and Escalante rivers are maintained, above Lake Powell's full pool elevation of 3100 feet, and depending upon lake elevation, these flowing reaches can extend many miles in the Glen Canyon NRA. b. Inflows: The inflow areas are artificially created areas formed as a result of the backing up of water after completion of the dam. Inflows are transition zones where river currents meet the lake. The estuary-like inflow area is characterized by turbidity, high productivity, and abundant fish life. The inflow is defined as that area where river current slows and then dissipates into the calm, flat water of the lake. There is often a sand or silt bar associated with the plunge point where the river enters the lake. The inflow area is transitory, moving up and downstream in response to changes in lake elevation. Hydraulic processes operating on silt deposits left by a receding lake form backwaters and habitats that may not have been present in the historic river channel, but which are utilized by early life stages of both native fish and sport fish. 10