7878 - Laserfiche WebLink

Home Browse Search

1996 Green River Discharge Monitoring Introduction This 1996 Green River discharge monitoring program (Mineral Bottom Gage) was an extension of the project initiated the previous year in Canyonlands National Monument at Queen Anne Bottom. The level logger gaging station was established in the Canyonlands reach of the Green River to support the scientific research efforts of the Recovery Program for the Endangered Fishes in the Upper Colorado River Basin. The level logger and accompanying staff gages were used by the Flooded Bottomlands Program to assess stage-discharge relationships in Canyonlands. ' The 1995 Flooded Bottomlands Program was a component of the Habitat Restoration Program and encompassed river channel cross section surveys, topographic surveys of the floodplain and side canyon bottomlands, discharge measurements and analysis of the river response to high flows. The Green River Discharge Monitoring Program was expanded during the 1996 high flow season to determine the flow hydrograph in various locations of the Green River system from the confluence of the Yampa River to the confluence of the Colorado River. Level loggers were installed at Mitten Park, Ouray National Wildlife Refuge, downstream of the White River, and Desolation Canyon. The Canyonlands level logger was also reinstalled at Queen Anne Bottom. Discharge measurements were collected to establish a rating curve for the level loggers. At each level logger a cross section was surveyed during each discharge measurement. A survey bar and cap was installed for replicating the cross section surveys. The cross section data, discharge measurements and rating curves are available for use in other research programs. Project Goals and Objectives The long term project goal is to establish a greater understanding of the progression of the seasonal high flow hydrograph in the Green River system in terms of peak discharge magnitude and frequency, timing and duration. This hydrologic data base will support management .decisions regarding timing and duration of upstream flow releases. In addition, the data base will enable quantification of flood wave attenuation, analysis of tributary inflow, identification of timing of the opening backwater habitat, and prediction of nursery habitat floodability. The project objectives were to establish discharge monitoring sites at intervals of approximately 75 miles in the Green River. In addition, discharge monitoring sites were selected to accommodate the major tributary inflows. A further objective was to provide discharge measurements with corresponding cross section surveys to support channel morphology investigations and bottomland floodability assessments. The collection of discharge measurements were made to establish rating curves for the level loggers. The resulting discharge hydrograph was then compared with the USGS river gages at Jensen and Green River, Utah. 1