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Charles A. Kaehler

Publications and source records attributed to Charles A. Kaehler.

7 recordsLinked to original sources
USGS2003

Tracing reclaimed water in the Menifee, Winchester, and Perris-South ground-water subbasins, Riverside County, California

As a component in the management of water resources in the Menifee, Winchester, and Perris-South subbasins in Riverside County, California, ponds are operated by the Eastern Municipal Water District for the temporary storage of reclaimed water that is produced by several regional water-reclamation facilities. A primary goal of this study was to evaluate the potential for using various ground-water constituents or characteristics as tracers of reclaimed water that has infiltrated from the storage ponds into the ground water in the three subbasins. A secondary goal was to estimate the degree to which the infiltrated reclaimed water has mixed with the native ground water. The evaluation of potential tracers and the estimation of mixing focused on data from wells located relatively close to the ponds. The most useful constituents and characteristics for evaluation of the fate and mixing of reclaimed water in the Menifee, Winchester, and Perris-South subbasins are major-ion composition, stable isotopes of hydrogen and oxygen, ultraviolet absorbance (UV-A), chloride concentration, and boron/chloride ratio plotted against chloride concentration. Emphasis in this study was placed on evaluating the utility of UV-A as a tracer and boron/chloride ratios in estimating the fraction of reclaimed water in ground water. In the Menifee subbasin, major-ion data, stable isotopes, chloride, UV-A, and boron/chloride ratio are all useful in identifying reclaimed water, and the results based on these indicators are consistent with each other. The results suggest that values of UV-A greater than or equal to 0.007 indicate the presence of reclaimed water in the Menifee subbasin. Ground-water samples with UV-A greater than 0.007 are estimated to consist of about 75 to 100 percent reclaimed water, on the basis of chloride-mixing calculations and boron/chloride-versus-chloride mixing calculations. In the Winchester subbasin, results based on the same factors used in the Menifee subbasin are less conclusive; nevertheless, UV-A can be used as a tracer. The results suggest that values of UV-A greater than 0.01 indicate the presence of reclaimed water. Values from 0.006 to 0.01 may indicate the presence of reclaimed water; however, water from wells not likely to have reclaimed water may also have UV-A values in this range. Ground-water samples with UV-A greater than 0.01 seem to contain about 25 percent reclaimed water (range 6 to 32 percent), on the basis of the consistency of the results of three types of mixing calculations--chloride alone, boron/chloride versus chloride, and UV-A. In the Perris-South subbasin, the potential tracers are not as conclusive in identifying reclaimed water in the subsurface as in the Menifee and Winchester subbasins. The less-conclusive results are a consequence of the multiple, spatially distributed sources of reclaimed water; the relative absence of wells close to the reclaimed-water pond; and the short period of operation (about 1 year) of the pond at the time of sampling. Mixing calculations suggest that ground-water samples with elevated UV-A values (greater than 0.01) in the Perris-South subbasin could contain as much as 40 to 65 percent reclaimed water.

Water-Resources Investigations Report↗
USGS2002

Long-term sand supply to Coachella Valley Fringe-toed Lizard Habitat in the Northern Coachella Valley, California

The Coachella Valley fringe-toed lizard ( Uma inornata ) is a federally listed threatened species that inhabits active sand dunes in the vicinity of Palm Springs, California. The Whitewater Floodplain and Willow Hole Reserves provide some of the primary remaining habitat for this species. The sediment-delivery system that creates these active sand dunes consists of fluvial depositional areas fed episodically by ephemeral streams. Finer fluvial sediments (typically sand size and finer) are mobilized in a largely unidirectional wind field associated with strong westerly winds through San Gorgonio Pass. The fluvial depositional areas are primarily associated with floodplains of the Whitewater—San Gorgonio Rivers and Mission Creek—Morongo Wash; other small drainages also contribute fluvial sediment to the eolian system. The eolian dunes are transitory as a result of unidirectional sand movement from the depositional areas, which are recharged with fine-grained sediment only during episodic floods that typically occur during El Niño years. Eolian sand moves primarily from west to east through the study area; the period of maximum eolian activity is April through June. Wind speed varies diurnally, with maximum velocities typically occurring during the afternoon. Development of alluvial fans, alteration of stream channels by channelization, in-stream gravel mining, and construction of infiltration galleries were thought to reduce the amount of fluvial sediment reaching the depositional areas upwind of Uma habitat. Also, the presence of roadways, railroads, and housing developments was thought to disrupt or redirect eolian sand movement. Most of the sediment yield to the fluvial system is generated in higher elevation areas with little or no development, and sediment yield is affected primarily by climatic fluctuations and rural land use, particularly livestock grazing and wildfire. Channelization benefits sediment delivery to the depositional plains upwind of the reserves by minimizing in-channel sediment storage on the alluvial fans. The post-development annual sediment yield to the Whitewater and Mission Creek—Morongo Wash depositional areas are 3.5 and 1.5 million ft 3 /yr, respectively, covering each depositional area to a depth of 0.2 to 0.4 in. Given existing sand-transport rates, this material could be depleted by eolian processes in 8 to 16 months, a rate consistent with the presence of persistent sand dunes. However, these depletion times are likely minimum estimates, as some eolian sand is seen to persist in the immediate vicinity of depositional areas for longer time periods. Transport rates may be reduced by the presence of vegetation and other windbreaks. Because they are perpendicular to prevailing winds, the infiltration galleries on Whitewater River trap fluvial and eolian sediment, reducing sediment availability. Also, the presence of the railroad and Interstate 10 redirect eolian sand movement to the southeast along their corridors,potentially eliminating the Whitewater depositional area as a sand source for the Willow Hole Reserve. Using directional wind data, we discuss the potential for eolian sand transport from the Mission Creek—Morongo Wash depositional area to Willow Hole.

California↗
USGS1998

Geohydrology of the Winchester Subbasin, Riverside County, California

The 20-square-mile Winchester structural subbasin is an alluvium-filled paleocanyon that is as much as 900 feet deep. The alluvial aquifer is composed of detrital material that generally ranges in size from clay to fine gravel; the fine and coarse materials are mixed in some places and inter- bedded in others. The apparent lenticularity of fine- and coarse-grained materials and differing water quality with depth indicate that the aquifer is partly or locally confined. A ground-water divide exists east of the town of Winchester. West of the divide, ground water moves toward and into the South Perris and the Menifee subbasins. East of the divide, ground water moves toward and into the Hemet subbasin. The components of flow direction in the Winchester?Hemet subbasins border area are complex: along the border, some water moves from the southwest corner of the Hemet subbasin into the Winchester subbasin and then eastward subparallel to the border before moving back into the Hemet subbasin. The direction of ground-water movement between the Winchester and Hemet subbasins, and the position of the ground-water divide in the central part of the Winchester subbasin, have changed with time. Prior to about 1974, ground water moved both eastward from the divide and westward from the Hemet subbasin toward a local depression of the water table caused by pumping in the eastern part of the Winchester subbasin. Comparison of spring 1970 and spring 1993 ground-water levels indicates a net rise of as much as 150 feet in the east end of the Winchester subbasin. For this same period, water levels rose about 3 to 20 feet in the western and central parts of the subbasin. Ground-water chemistry in the Winchester subbasin and adjacent subbasins varies areally and vertically. In general, sodium, calcium, chloride, and sulfate are dominant ions. Water quality is generally poor: dissolved-solids concentration exceeded 2,000 milligrams per liter throughout much of the subbasin and was highest west of the town of Winchester. Eastward along the subbasin axis (toward the Hemet subbasin), the dissolved-solids concentration decreases and the pH increases (generally greater than 7.0). Samples from two multiple-well monitoring sites at the west and east ends of the subbasin indicate that the best quality water (dissolved-solids concentrations of 395 and 483 milligrams per liter) is from the deepest wells (perforated near the alluvium- bedrock contact). Samples from the deeper wells in the eastern part of the Winchester subbasin are similar in water type to a sample from a well in the western part of the Hemet subbasin, which suggests that the water may have flowed from the Hemet subbasin; alternatively, the chemistry may reflect the influence of good-quality water flowing from the fractured bedrock basement to the alluvium in the eastern part of the Winchester subbasin. In addition, the potential problem of poor-quality water moving from the Winchester subbasin into the Hemet subbasin may not exist at all depths; fair- to good-quality water may be present below a depth of about 450 feet. Dissolved-solids concentrations in the southwest part of the Hemet subbasin ranged from about 900 milligrams per liter at well 5S/1W-19Q1 about one-quarter mile north of the Winchester?Hemet subbasin boundary to about 3,500 milligrams per liter at well 5S/2W-24C2 near the bedrock outcrops southeast of the Lakeview Mountains. High dissolved-solids concentration in the vicinity of well 5S/2W-24C2 most likely is a result of dissolution of constituents from the aquifer matrix, evaporative processes, and agricultural practices that occur in that vicinity rather than a result of flow from the Winchester subbasin. Aquifer-test results indicate that the transmissivity is about 950 feet squared per day in the eastern part of the Winchester subbasin near the boundary with the Hemet subbasin and about 72 feet squared per day in the western part of the subbasin near the boundary with th

California↗
USGS1997

Comparison of 1972 and 1996 water levels in the Goleta central ground-water subbasin, Santa Barbara County, California

Ground-water levels for 1996 were compared with 1972 water levels to determine if a "drought buffer" currently exists. The drought buffer was defined previously, in a litigated settlement involving the Goleta Water District, as the 1972 water level in the Central ground-water subbasin. To make this deter mination, a network of 15 well sites was selected, water levels were measured monthly from April through December 1996, and the 1996 water-level data were compared with1972 data. The study was done in cooperation with the Goleta Water District. The 1972-1996 water-level-altitude changes for corresponding months of the comparison years were averaged for each network well. These averaged changes ranged from a rise of 9.4 ft for well 2N2 to a decline of 45.0 ft for well 8K8. The results of the comparison indicate a rise in water level at 1 site (well 2N2) and a decline at 14 sites. The mean of the 14 negative average values was a decline of 24.0 ft. The altitude of the bottom of well 2N2 was higher than the bottom altitudes at the other network sites, and this well is located a few feet from a fault that acts as a hydrologic barrier. The results of the water-level comparison for the Central subbasin were influenced to some unknown degree by the areal distribution of the set of wells selected for the network and the vertical dis tribution of the perforated intervals of the wells. For this reason, the mean water-level change--a decline of 21.8 ft--calculated from the averages of the month-to-month changes for the 15 network sites, should be used with caution. In addition, the number of usable individual monthly comparison measurements available for an individual site ranged from one to nine, and averaged six. Therefore, a weighted mean of the monthly averages was calculated on the basis of the number of comparison measurements available for each site. The weighted mean is a decline of 20.9 ft. All Central subbasin wells that were idle (that is, were not being pumped) when measured in 1972 and that were measureable in 1996 were included in the network. Therefore, the network is the most inclusive possible, given the available data. The objective of the study strictly was to compare 1972 and 1996 water levels in the Central sub basin, and the conclusion is that, overall, 1996 water levels are lower than 1972 levels. In general, hydro graphs for selected network wells indicate stable or rising water levels during 1972-83, declining levels during 1984-92, and rising water levels during 1993-96.

Water-Resources Investigations Report↗
USGS1996

Well-construction, water-quality, and water-level data, and pond-infiltration estimates, for three ground-water subbasins, Riverside County, California

Reclaimed water in the Eastern Municipal Water District of Riverside County,California, is used within the service area for agricultural irrigation.Owing to the seasonal demand for reclaimed water, storage/infiltration ponds were constructed in the Winchester, Menifee, and south Perris subbasins.Reclaimed water infiltrates from these ponds and enters the groundwater system. Little is known of the effects of the reclaimed water on groundwater quality. In cooperation with the Eastern MunicipalWater District, the U.S. Geological Survey began a study in 1995 to determine the quantity and fate of reclaimed water percolating from these storage ponds. Data compiled during the first phase of this study are presented in this report. Field reconnaissance of the Winchester, Menifee, and south Perris subbasins indicated the existence of many wells. Wellconstruction data for 115 of these wells were tabulated. Available historical waterquality and waterlevel data for 178 wells in the subbasins also were tabulated. In addition, water levels in 86 wells were measured during the spring and autumn of 1995. On the basis of these data, waterlevel contour lines were drawn and the direction of groundwater flow was determined.Three lithologic sections through the subbasins were constructed from drillers' logs of 26 wells.

Water-Resources Investigations Report↗
USGS1991

Ground-water data for San Nicolas Island, California, 1989-90

In an effort to gain geohydrologic knowledge and to increase the availability of ground water to the U.S. Navy on San Nicolas Island, nine test wells were drilled by the U.S. Geological Survey in 1989 and one production well was drilled by the U.S. Navy in 1990. One of the nine test wells was dry, five produced less than 10 gallons of water per day, two produced between 20 and 30 gallons per day, and one produced 400 gallons per day. The production well produced about 900 gallons per day. Water samples were collected from eight wells during 1989-90 and analyzed for concentrations of major dissolved inorganic ions and nutrients. Five of the sampled wells were constructed in 1989, one was constructed in 1990, and two were constructed prior to 1989. Data from the study are presented in tables and graphs. Included are geophysical, lithologic, and well-construction data and results obtained from well-pumping tests and from the chemical analysis of water from selected wells.

California↗