WSP06075 - Laserfiche WebLink

Home Browse Search

002890 and unit duration at one point in this channel wi 11 result in a specific flow response, or unit response,at a downstream location. The method has been used successfully for a number of streams. For the Yampa River basin, the method might be used to simulate daily discharge at sites where data of short duratIon are available usin9 upstream or downstream sites with longer records. For most cases, a common data period to both sites wIll be used to cal ibrate the model parameters. After a uniform data base has been establ ished for several locations, streamflow can be estimated at locations where data are not available. This is accomplished by reapplying the unIt-response routing technIque, or by using basin-characteristIc relationships. As an alternative or supplemental method, selected streamflow records of short duration may be extended using correla- tIon procedures described by Fiering (1963), and Matalas and Jacobs (1964). These procedures may improve the population estimates of the mean and variance of streamflow data. This would be helpful in evaluating the potential use and benefits of additional storage reservoirs and for determining benefits of ad- ditIonal streamflow data, Reservoir modeling.--Several small reservoirs are located on tributaries of the Yampa River. Generally, these were built. for recreation, livestock wa- terin9, and irrigation. There are numerous reservoirs in the planning stages which have intended uses of I rrigation, hydroelectric power, and cool ing water for power plants. The present reservoirs are operated with uncontrolled over- flow structures, whereas some of the larger planned reservoirs will be oper- ated with release schedules designed to optimize power generation or irrIga- tion use. The hydrologic effects of selected present and planned reservoirs having capacities of 5,000 acre-feet (6,2x106 m3) or more will be simulated during the basin assessment. Plans include the use of reservoir-routing techniques described by Rutler and Engstrom (1964) to simulate flow conditions downstream from the reservoir for natural and controlled conditions. There are several operational reservoir-routing model pro9rams now available which could be used, Program HEC-3, developed by the U.S. Army Corps of Engineers (1968), Hydrolog- ic Engineering Center, and SIMYLD-11, developed by the Texas Water Development Board (1972), are two that will be considered. Both models are designed to simulate a system of reservoirs subject to a specified hydrology and time se- quence of demands, In most cases, the models operate on a monthly-Increment flow basis. Both models also allow the input of existing or planned operating schedules for the reservoirs. In addition, the HEC-3 program can consider re- lease schedules for reservoirs to be operated for power generation, Models also exIst that could be used to study the operation of Individual reservoirs, For some of the stream reaches, the reservoIr models will be com- bIned with the stream models, previously described, to generate streamflow data at some desired downstream location. Snowmelt-runoff modeling.--The dominant part of streamflow in the Yampa River basin is contrIbuted by snowmelt runoff from the mountainous areas .in the eastern part of the basin, Snowmelt occurs consistently between late April and early July, with the highest monthly flows occurring during May and June. W. V, Tangborn (U,S, Geological Survey, Tacoma, Wash.) currently Is applying snowmelt-runoff modelIng techniques to the upper Yampa River basin 17