FLOOD08553 - Laserfiche WebLink

Home Browse Search

. . Ridgway Dam and Reservoir maintains a minimum pool for recreation and sedimentation and provides minimum flows for fisheries. Recreation facilities are provided along the north, south, and west sides of the reservoir. Ridgway State Park, managed and operated by the Colorado Division of Parks and Outdoor Recreation, offers a variety of recreational opportunities with 1,000 surface acres of water and over 2,200 land acres. . 3.0 ALTERNATIVES . 3.1 No Action. The no-action alternative assumes that no Federal action would be taken to adopt and implement a water control manual that includes flood control operations for Ridgway Dam and Reservoir. The USBR would likely operate the project under a preliminary water control plan that is already in place. . The USBR is required to operate the project for flood control as prescribed on an existing water control diagram (see Plate 3). A stage-frequency curve developed by the USBR shows how current operation affects reservoir levels. The curve in Figure 1 shows the frequency of the reservoir filling. Basically, the reservoir fIlls sooner, holds more water and more often, but leaves less space for flood storage, The frequency in which the reservoir would reach gross pool would be higher. with a higher risk of spilling and possibly causing flooding downstream from the dam, The no-action alternative is in violation of congressional authorization and, therefore, may require project re-authorization. . . 3.2 Adopt Water Control Manual. With this alternative, a Federal action would be taken to formalize and adopt the water control manual and implement flood control operations as described in the water control diagram for Ridgway Dam and Reservoir. The flood control objectives in the diagram include: . . To protect the area in the flood plain against probable snowmelt and thunderstorm floods. . To control flows in the Uncompahgre River downstream from Ridgway Dam to existing channel capacity. At the Colona stream gage, this would be 2,000 cfs. . . To provide the maximum amount of water conservation storage without impairment of the flood control functions of the reservoir, . In achieving these objectives, forecasting of snowmelt runoff is important. When the snowpack is at or above normal, a close daily watch of flows is necessary. 4 .