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J.G. Rankl

Publications and source records attributed to J.G. Rankl.

5 recordsLinked to original sources

Relations between total-sediment load and peak discharge for rainstorm runoff on five ephemeral streams in Wyoming

Total-sediment loads transported by ephemeral flows are a function of rainstorm energy and peak discharge. Rainstorm energy, estimated by rainfall intensity, is the primary mechanism for soil-particle detachment. Vegetation, soil cohesiveness, and land slope also are related to the amount of sediment detached, but these factors remain nearly constant, except for seasonal or human-induced changes in vegetation. Thus, the largest variability in total-sediment loads is the result of variability in rainstorm energy. The magnitude of the peak discharge in a stream from a runoff-producing rainstorm is a function of the intensity and volume of rainfall. The greater the rainfall intensity for the same volume of rainfall, the larger the peak discharge. Therefore, for each drainage area a relation exists between the total-sediment load for a rainstorm and the peak discharge for the rainstorm, because both are a function of rainstorm energy. Total-sediment loads for runoff-producing rainstorms were computed from sample data collected at five ephemeral streams in semiarid areas of Wyoming. Regression analyses were used to develop equations relating total-sediment load to the peak discharge. Coefficients of determination ranged from 89 to 97 percent. Average standard errors ranged from 35 to 94 percent. The slopes of the lines defined by the equations were not different at the 95-percent level of significance, but the intercepts were significantly different for the five streams.

Water-Resources Investigations Report

Use of dye tracing in water-resources investigations in Wyoming, 1967-94

During 1967-94, the U.S. Geological Survey made numerous applications of dye tracing for water-resources investigations in Wyoming. Many of the dye tests were done in cooperation with other agencies. Results of all applications, including some previously unpublished, are described. A chronology of past applications in Wyoming and a discussion of potential future applications are included. Time-of-travel and dispersion measurements were made in a 113-mile reach of the Wind/Bighorn River below Boysen Dam; a 117-mile reach of the Green River upstream from Fontenelle Reservoir and a 70-mile reach downstream; parts of four tributaries to the Green (East Fork River, 39 miles; Big Sandy River, 112 miles; Horse Creek, 14 miles; and Blacks Fork, 14 miles); a 75-mile reach of the Little Snake River along the Wyoming-Colorado State line; and a 95-mile reach of the North Platte River downstream from Casper. Reaeration measurements were made during one of the time-of-travel measurements in the North Platte River. Sixty-eight dye-dilution measurements of stream discharge were made at 22 different sites. These included 17 measurements for verifying the stage-discharge relations for streamflow-gaging stations on North and South Brush Creeks near Saratoga, and total of 29 discharge measurements at 12 new stations at remote sites on steep, rough mountain streams crossing limestone outcrops in northeastern Wyoming. The largest discharge measured by dye tracing was 2,300 cubic feet per second. In karst terrane, four losing streams-North Fork Powder River, North Fork Crazy Woman Creek, Little Tongue River, and Smith Creek-were dye-tested. In the Middle Popo Agie River, a sinking stream in Sinks Canyon State Park, a dye test verified the connection of the sink (Sinks of Lander Cave) to the rise, where flow in the stream resumes.

Water-Resources Investigations Report

Estimates of monthly streamflow characteristics at selected sites, Wind River and part of Bighorn River drainage basins, Wyoming

Monthly streamflow records from gaging stations with more than 5 years of record were extended to a 50-year base period, 1941-90, using a mixed- station, record-extension model. Monthly streamflow characteristics were computed from the extended record. Four statistical methods--basin characteristics, active-channel width, concurrent measurement, and weighted average were used to estimate monthly streamflow characteristics at ungaged sites and at streamflow-gaging stations with fewer than 5 years of record. Linear- regression models were used with the basin characteristic and active-channel-width methods to define the relations between the monthly streamflow characteristics and physical basin, climatic, and channel characteristics. The concurrent-measurement method used a Maintenance of Variance Extension, Type 1 curve-fitting technique to correlate discharge at active streamflow-gaging stations, which had computed streamflow characteristics, with discharge measured at ungaged sites. The weighted-average method is a weighted combination of estimates from any two or all three of the other methods. For the basin-characteristics method, the standard errors of estimate ranged from 37 to 83 percent and for the active-channel-width method, 34 to 100 percent. Standard errors for the concurrent- measurement method ranged from 27 to 151 percent. The standard error for the weighted-average method, ranged from 18 to 82 percent, which was lower than any individual method. Application of the equations for estimating monthly streamflow characteristics is limited to perennial streams with physical-basin, climatic, and active channel- width characteristics that are within the range of values used in the study. The equations are not applicable to estimate flow for ephemeral streams.

Water-Resources Investigations Report

Analysis of sediment production from two small semiarid basins in Wyoming

Data were collected at two small, semiarid basins in Wyoming to determine the relation between rainfall, runoff, and sediment production. The basins were Dugout Creek tributary and Saint Marys Ditch tributary. Sufficient rainfall and runoff data were collected at Dugout Creek tributary to determine the source of sediment and the dominant sediment production processes. Because runoff from only one storm occurred in Saint Marys Ditch tributary, emphasis of the study was placed on the analysis of data collected at Dugout Creek tributary. At Dugout Creek tributary, detailed measurements were made to establish the source of sediment. To determine the quantity of material removed from headcuts during the study, two headcuts were surveyed. Aerial photographs were used to define movement of all headcuts. The total quantity of sediment removed from all headcuts between September 26, 1982, and September 26, 1983, was estimated to be 1,220 tons, or 15%-25% of the estimated total sediment load passing the streamflow-gaging station. A soil plot was used to sample upland erosion. A rainfall and runoff modeling system was used to evaluate the interaction between the physical processes which control sediment production. The greatest change in computed sediment load was caused by changing the parameter values for equations used to compute the detachment of sediment particles by rainfall and overland flow resulted in very small changes in computed sediment load. The upland areas were the primary source of sediment. A relationship was developed between the peak of storm runoff and the total sediment load for that storm runoff. The sediment concentration used to compute the total sediment load for the storm runoff was determined from sediment samples collected by two automatic pumping samplers. The coefficient of variation of the relationship is 34% with a 0.99 correlation coefficient. (Author 's abstract)

Water-Resources Investigations Report