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Stanley P. Sauer

Publications and source records attributed to Stanley P. Sauer.

6 recordsLinked to original sources
USGS1978

Recent and projected changes in Dead Sea level and effects on mineral production from the sea

Hydrologic data for the Dead Sea area were reviewed to assess the probable magnitude and rate of change of the water level of the Dead Sea. Historical average annual Dead Sea levels range from a minimum of 399.4 meters below sea level in about 1818 to a maximum of 388.6 meters below in 1896. Present levels are rapidly approaching the historical low. There is a close correlation between Dead Sea level and accumulated departure from the mean of long-term rainfall except for the most recent period since 1964. During that period rainfall has been near the long-term average but water levels have continued to decline, in part due to abstractions for irrigation in the Jordan River basin. The dissolved-solids concentration of Dead Sea water presently is approximately 322,000 milligrams per liter and is generally well mixed throughout. This concentration is at the saturation level, resulting in continuous precipitation of some salts. The increase in dissolved solids to the present high concentration has resulted in an evaporation rate less than that estimated in previous reports. Evaporation rate from the North Basin is estimated at 1,310 millimeters per year at present. The evaporation rate from the South Basin was not estimated due to extensive existing or planned modifications for mineral production facilities. Water budget computations were performed at various inflow rates in order to project water-level changes for 50 years. Computations assumed closure of the South Basin by existing and proposed mineral extraction facilities. The projected 50-year changes ranged from a decline of 51 meters with no inflow from any sources to a rise of 10.2 meters when average annual inflow from the Jordan River was 750 cubic hectometers. An average annual inflow to the Sea of 900 cubic hectometers from all sources is required to stabilize the Sea at the present level. Principal impact of declining water levels on proposed potash production facilities in Jordan would be an increase in power requirements. A cursory review of a proposed plan to divert water from the Mediterranean Sea into the Dead Sea to generate electric power and stabilize water levels indicates a very limited impact on chemical, physical, and ecological characteristics of the Dead Sea in the near future. Water-budget computations indicate that if all but 200 cubic hectometers of tributaries' waters were utilized for irrigation and other purposes, a maximum diversion of 700 cubic hectometers per year into the Dead Sea would be possible without significantly raising long-term average water levels.

Dead Sea↗
USGS1972

Factors contributing to unusually low runoff during the period 1962-68 in the Concho River Basin, Texas

To determine the reasons for the unusually low runoff in the Concho River basin during the period 1962-68, the physical developments and climatic changes in the basin were identified and related to changes in the regimen of streamflow. Land use, brush infestation, and land-treatment practices have not caused significant changes in the rainfall-runoff relationship. The use of surface water for irrigation has increased very little during the past 70 years, and although the use of ground water for irrigation has greatly increased in the past 25 years, springflow has not been significantly diminished. The base flow of the streams is materially reduced by surface-water irrigation diversions. Diversions for municipal and industrial use have increased rapidly, but these diversions affect only the streamflow downstream from San Angelo. Statistical analyses showed the annual rainfall to be highly variable, with little serial correlation. Records of rainfall during the period 1943-68 are significantly different in character from previous long-term records. The frequency of monthly rainfall equal to or greater than 2.0 inches during the period 1943-68, and especially during the period 1962-68, was significantly less than the long-term averages. Analyses of annual runoff data, adjusted for depletions, show large variations in annual runoff. Coefficients of variation ranged from 0.8 to 1.4, and first-order serial correlations ranged from 0.01 to 0.28. The estimated recurrence interval of the 1962-68 drought is about 200 years. The analyses of rainfall-intensity and runoff data indicate that the basic cause for the relatively low runoff during the period 1962-68 was the lack of high-intensity, long-duration storms rather than any physical changes or agricultural practices in the watershed

Texas↗
USGS1970

Hydrologic effects of floodwater-retarding structures on Garza-Little Elm Reservoir, Texas

The Texas District of the Water Resources Division of the U.S. Geological Survey has collected and analyzed hydrologic data since 1953 to define the effects of systems of floodwater-retarding structures on downstream water and sediment yield. The district project includes 11 study areas ranging from 18 to 80 square miles in size and from 0 to 67 in percent of study area controlled by floodwaterretarding structures. The 11 study areas are within that part of Texas where the west-to-east average annual runoff ranges from about 2 to 7 inches. This report presents results of analyses, development of methodolgy, and results of application of methods for defining the downstream effects of systems of floodwaterretarding structures. Annual inflow to and outflow from the system of floodwater-retarding reservoirs in seven of the 11 study areas were found to be related by the equation: O=0.98/ 0.68, where O is annual outflow, in inches, and / is annual net inflow, in inches. Transmission loss of structure outflow to the downstream study-area stream-gaging station was determined and compared with the transmission loss of natural flood flow between tandem stream-gaging stations on Denton Creek, a tributary to Elm Fork Trinity River above Dallas. Trap efficiency of most floodwater-retarding structures was found by the U.S. Soil Conservation Service to be about 97 percent. Downstream increases in suspended-sediment concentration in the outflow were found to be large in a study area with mostly silt and clay sediments, but even a large increase in suspendedsediment concentration did not represent a significant quantitative pickup of sediment by the outflow water. Water consumption in floodwater-retarding reservoirs from the combined actions of evaporation, evapotranspiration, and seepage was found to be as much as twice the average annual consumption attributable to evaporation alone. Average annual consumption in reservoirs in the seven study areas analyzed ranged from 1.57 inches of equivalent runoff in the easternmost study area, where annual runoff averaged 6.96 inches, to 0.77 inch of equivalent runoff in the westernmost study area, where the average annual runoff was 2.35 inches. The effect of consumption on downstream flow is partially offset by rainfall on pool surface. Studies covering as much as 15 years of streamflow record at the stream-gaging stations that gage outflow from the Deep and Honey Creek study areas indicated no increase in base flow. Multiple-linear-regression techniques were used in developing methodology to determine reservoir consumption in seven study areas. The physical and climatic fnctors influencing consumption were grouped as variables in regard to their relative effect on the actions of evaporation, evapotranspiration, and seepage. The resulting generalized equation was then used in synthesizing the consumptive effects of a planned system of 162 floodwater-retarding reservoirs controlling 26 percent of a 1,660-square-mile drainage basin upstream from a major water-supply reservoir. The analyses were based on the assumption that all water consumed at the floodwater-retarding reservoirs would have reached the downstream watersupply reservoir. Water-sediment discharge relationships were derived for the runoff into the structures as well as for the runoff through and below the structures. A mathematical response model of the floodwater-retarding reservoir systems and the entire drainage basin was computer programed to yield monthly water and sediment inflow to the water-supply reservoir. Results of the response model showed that with full development, depletion of annual yield to the large reservoir would be as much as 10 percent in the early years; but after the permanent pools of the floodwater-retarding structures had mostly filled with sediment, depletion of annual yield would be generally less than 1 percent. The depletion of yield to Garza-Little Elm Reservoir during the 39-year synthesized period of study was estimated as 296,800 acre-feet out of 18,256,000 acre-feet total yield. During the same period, the floodwater-retarding structures were estimated to have kept 19,700 acre-feet of sediment from being deposited in the reservoir. "Firm"- or "critical"-yield studies were made of the large reservoir on the basis of two sets of conditions : with floodwater-retarding structures in the drainage basin, and without such structures. Results of the firm-yield studies indicated that with full development, annual firm yield would be initially reduced by 10 percent. After 30 or more years, when the permanent pools of the floodwaterretarding reservoirs would be mostly filled with sediment, the firm yield would be almost the same with or without the upstream development.

Texas↗