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L.C. Dutcher

Publications and source records attributed to L.C. Dutcher.

At least 19 recordsLinked to original sources
USGS1972

Ground-water outflow, San Timoteo-Smiley Heights area, upper Santa Ana Valley, southern California, 1927 through 1968

The San Timoteo-Smiley Heights area is in the upper Santa Ana Valley, San Bernardino and Riverside Counties, Calif., where the Yucaipa and San Timoteo-Beaumont ground-water basins border Bunker .Hill basin on the south between the San Jacinto and San Andreas faults. The area is broken by numerous faults, the topography is rough, and in a large part of the area few wells had been drilled prior to 196S. The alluvial deposits, which constitute the aquifers in the area, range in thickness from 0 where they lap onto exposed bedrock hills to about 1,000 feet. Beneath the southern part of the area near the San Jacinto fault the total thickness of alluvial and lacustrine deposits may be as much as 6,000 feet. The purpose of this study was to estimate ground-water outflow by an indirect method not involving balancing of the hydrologic budget. For this purpose it was necessary to estimate the permeability of the aquifer materials, the average annual hydraulic gradient, and the cross-sectional area through which the flow occurs; these values were estimated for five segments along a line of section between the San Jacinto fault and Crafton Hills. To provide data for the outflow estimates, several miles of reflection and refraction seismic traverses were made along and across the outflow section. Nineteen deep and shallow test holes were drilled; one of the deep test holes and several existing wells were pumped to obtain data on aquifer permeability. The estimated average permeabilities of the aquifer materials range from 5 gallons per day per square foot for the lower part of the San Timoteo beds of Frick (1921) and 40 gallons per day per square foot for the older alluvium to 220 gallons per day per square foot for the upper part of the San Timoteo beds. The estimated outflow in 1927 was 8,150 acre-feet. By 1967 the estimated total outflow was 5,350 acre-feet, a reduction of approximately 34 percent. During the 12-year period 1956 through 1967, however, the annual outflow decline has been considerably less than the average for the 41-year period 1927 through 1967, and the decline as of 1968 was probably about 30-35 acre-feet per year.

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USGS1963

Geologic and hydrologic features of the San Bernardino area, California; with special reference to underflow across the San Jacinto fault

This is the second in a series of interpretive reports on subsurface outflow from the ground-water basins of San Bernardino County, Calif., prepared by the U.S. Geological Survey in cooperation with the San Bernardino County Flood Control District. One principal purpose of the study was to estimate the ground-water outflow from the Bunker Hill basin to the Rialto-Colton basin across the San Jacinto fault, which, except locally, forms a nearly impermeable boundary between the two basins. In addition, the report deals qualitatively with the geology, the fault barriers that divide the area into several ground-water basins, the physical nature and degree of imperviousness of the barriers, the occurrence and movement of ground water and fluctuations of water level in the basins, and the chemical quality of surface and ground waters in the San Bernardino area. The report includes a geologic map and sections, water-level-contour maps and profiles, and hydrographs of selected well. The Santa Ana River, the principal stream, flows generally westward across the area. Channels of the river and its tributaries overlie a large irregular structural depression filled with alluvial deposits ranging in age from late Tertiary to Recent and forming a valley bounded on the north by the San Gabriel Mountains, on the east by the San Bernardino Mountains, and on the south by an irregular group of hills. Large alluvial fans underlie most of the area, but its landforms also include alluvial benches and terraces near the mountains, stream channels, and elongate hills, ridges, and scarps along the trace of the San Jacinto fault, which strikes northwestward across the valley about in the center of the area. This fault and others divide the area into ground-water basins, which include the Bunker Hill, Rialto-Colton, upper and lower Lytle and Chino basins. The water-bearing deposits include the following units: the younger alluvium. of Recent age, which occupies principally the backfilled channels beneath the Santa Ana River and its tributaries and through which ground water moves from Bunker Hill basin to Rialto-Colton basin; the older alluvium, of Pleistocene age, which is the principal water-bearing unit of the area and yields water to more than a thousand wells; and continental deposits of Tertiary to Quaternary age, which crop out along the southern margin of the area and locally along the San Gabriel Mountains on the north. The younger alluvium attains a maximum thickness of about 125 feet beneath the Santa Ana River south of San Bernardino. Locally in the Bunker Hill basin it is composed of two members, an upper member of relatively impermeable clay and a lower member of highly permeable material in which water is confined by the upper member. The older alluvium locally has a known thickness greater than 700 feet; elsewhere in the San Bernardino Valley it may exceed 1,400 feet. Locally, where ground water is confined in Bunker Hill basin, the older alluvium is divided into three permeable water-bearing zones separated from each other and from the younger alluvium above by less permeable zones. In parts of Chino and Rialto-Colton basins the alluvium consists of a coarse-grained facies along a former course of a major stream that is interfingered with and overlain by relatively fine-grained deposits. The permeability of the younger alluvium in the area beneath the Santa Ana River downstream from the San Jacinto fault was determined from tests to be about 2,700 gallons per day per square foot. The permeability of the coarse water-yielding materials of the older alluvium several miles downstream was estimated from tests to be about the same magnitude. Rocks that yield practically no water include continental rocks of Tertiary age, which are not exposed in the area but are tapped by wells in Rialto-Colton basin, and crystalline and metamorphic rocks of pre-Tertiary age that form the bedrock of the area.

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USGS1962

Data on wells in the Edwards Air Force Base area, California

The data presented In this report were collected by the U.S. Geological Survey as a phase of the investigation of ground-water geology and hydrology of the Edwards Air Force Base area. The study was made in cooperation with the Department of the Air Force but also was coincident with the U.S. Geological Survey investigation of water wells and general hydrologic conditions throughout much of the desert region of southern California. The overall study of general hydrologic conditions in the desert is part of a cooperative program with the California Department of Water Resources.

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