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Omar J. Loeltz

Publications and source records attributed to Omar J. Loeltz.

15 recordsLinked to original sources
USGS1979

Relation between proposed developments of water resources and seepage from the All-American Canal, eastern Imperial Valley, California

A two-layer digital model designed for this study indicated that sealing of the Coachella branch of the All-American Canal would cause an eventual increase in seepage from the All-American Canal of about 15,000 acre-feet annually. Sealing of both the Coachella Canal and the segment of the All-American Canal between Pilot Knob and Drop 1 would result in a lessening of seepage rates from the All-American Canal of 57,000 acre-feet in 1985, but of only 39,000 acre-feet in 2030. Sealing both the Coachella and the All-American Canals would reduce the outflow to Mexicali Valley from 120,000 acre-feet in 1980 to less than 9,000 acre-feet in 2030. The model also indicated that if only the Coachella Canal were sealed, a little less than 40 percent of water pumped from proposed well fields near the All-American Canal ultimately would be derived from increased seepage from the All-American Canal; between 50 and 60 percent of the water pumped would be water that otherwise would flow to Mexicali Valley.

California↗
USGS1964

Evaluation of hydrogeology and hydrogeochemistry of Truckee Meadows area, Washoe County, Nevada

Practically all the ground water of economic importance in the Truckee Meadows area, an alluviated intermontane basin in western Nevada is in the valley fill, which consists of unconsolidated and partially consolidated sedimentary deposits. The Mesozoic and Cenozoic consolidated rocks of the mountains bordering the valley contain some water in fractures and other openings, but they have virtually no interstitial permeability. The permeability of the valley fill is extremely variable. The Truckee Formation, which is the oldest deposit of the valley fill, yields very little water to wells. Permeable lenses of sand and gravel in the valley fill that are younger than the Truckee Formation yield moderate to large amounts of water to wells. The estimated average annual recharge to and discharge from the groundwater reservoir is 35,000 acre-feet. About 25,000 acre-feet of the recharge is from the infiltration of irrigation water diverted from the Truckee River. Most of the discharge is by evapotranspiration and by seepage to ditches and streams. Some water in the area is unsuitable for many uses because of its poor chemical quality. Water in the Steamboat Springs area is hot and has high concentrations of chloride and dissolved solids. Both water draining areas of bleached rock and ground water downgradient from areas of leached rock have high concentrations of sulfate and dissolved solids. Surface water of low dissolved-solids content mixes with and dilutes some highly mineralized ground water. Increased pumping in discharge areas will help to alleviate waterlogged conditions and will decrease ground-water losses by evapotranspiration. Increased pumping near the Truckee River may induce recharge from the river to the ground-water system.

Water Supply Paper↗
USGS1954

Hydraulic characteristics of aquifers penetrated by irrigation wells in the vicinity of Orovada, Humboldt County, Nevada, 1953

During the period April 21-23, 1953, a pumping test was made on several irrigation wells penetrating alluvium about a mile southwest of Orovada, Nev., in order to determine the hydraulic characteristics of the aquifers commonly penetrated by wells in that vicinity. The test was made by the writer, engineer, and J.L Poole, geologist, United States Geological Survey, as part of an investigation of the ground-water resources of Nevada being by the U.S Geological Survey in cooperation with the State Engineer. Much recent interest in the development of underground water by pumping in the Orovada area made it desirable to make the pumping test in order to obtain data that might be helpful in the proper planning of future development.

Nevada↗