Purpose and Scope: The purpose of this study was to evaluate the geohydrologic characteristics that influence sustained artificial recharge and to determine long-term infiltration rates in the northern part of Chino ground-water basin. Results of this study will help management to design and implement a recharge-recapture system in Chino Basin. Nine test holes were drilled, long-term infiltration tests were made, and drillers' logs and water-level data were evaluated to determine the probable effects of recharging the ground-water basin. The study was concentrated in the northern part of Chino Basin, where recharge is proposed.

From purpose and scope: The purpose of this study was to update hydrologic data and refine understanding of the hydrologic system within the San Dieguito, San Elijo, and San Pasqual hydrologic subareas in San Diego County, Calif., and to evaluate the suitability of these areas for reclaimed water use.

From introduction: The purpose of this report is to compile the available geologic information on the Kettleman City area of the Central Valley that would aid others in the proper management of the valley's ground-water resources.

Abstract: Sacramento County expected to begin operation of the Sacramento Regional Wastewater Treatment Plant in 1982. The California State Water Resources Control Board has ruled that the plant will not be allowed to release effluent into the Sacramento River when flow in the river is 4,000 cubic feet per second or less. Depending on tide condition, flows less than 4,000 cubic feet per second may occur either once or twice during each 24-hour 50-minute tide cycle when the daily mean flow is less than about 12,000 cubic feet per second. Daily mean flows less than 12,000 cubic feet per second occur about 28 percent of the time. Riverflow at the plant outfall is monitored by an acoustic streamflow measuring system. Regulation of effluent released from the plant will normally be based on real-time flow data computed by the acoustic system. A graphical method for determining the occurrence and duration of flows of 4,000 cubic feet per second and less was developed as a backup system to be used if a temporary failure in the acoustic system occurs.

From introduction: The purpose of this investigation is to provide the additional geohydologic information needed for Monterey County to develop plans for the optimum utilization of its water resources--particularly in the Prunedale and Aroms areas.

Purpose and scope: The U.S. Marine Corps conducts training maneuvers in the study area. Lack of a local source of water has severely limited the utilization of the area. In the past, limited quantities of water have been transported to the area by truck or helicopter. The purpose of this study was to determine the feasibility of obtaining a supply of ground water in the area for use when field maneuvers are being conducted. The major effort for this study was concentrated on the part within the Marine Corps base boundary. The study involved the assessment of ground-water quality, ground water in storage, and aquifer characteristics.

From purpose and scope: This report includes a description of the geohydrologic features of the different aquifers; a definition of source, occurrence, movement, and quality of the ground water; and an estimation of the current pumpage and ground-water storage.

From Purpose and Scope: The objectives of this study are: (1) to define, both qualitatively and quantitatively, the clogging processes associated with injection, and (2) to determine the three-dimensional migration paths of injection water and native ground water.

From purpose and scope: This report describes the effect of land application of effluent from wastewater treatment plants on ground-water quality in the Livermore-Amador Valley. The report focuses on five wastewater application areas contiguous to or near following wastewater treatment plants: Livermore, Pleasanton, Dublin-San Ramon Services District (was Valley Community Services District), Castlewood Corporation, and Veterans Administration Hospital.

From purpose and scope: The purpose of this study is to describe water-quality conditions in Shasta Lake and in major tributaries to the lake. The study involved the collection and interpretation of historical, hydrologic, and water-quality data collected during intensive and routine monitoring efforts.

Purpose and scope: The purpose of this study was to develop a method for estimating the amount of subsurface return flow to the Colorado River in the Yuma area. This report presents a method that permits an approximate accounting of ground-water return flow from each side of the Colorado River in Yuma reach. The method presented in this report was developed specifically for application in the Yuma area. The validity of the assumptions inherent in the method was evaluated on the basis of the local hydrologic system. The applicability of the method to other hydrologic systems is not addressed in this report.

Purpose and scope: The purpose of this study was to develop a method for estimating the amount of subsurface return flow to the Colorado River in the Yuma area. This report presents a method that will permit an accounting of ground-water return flows from each side of the Colorado River in the Yuma reach. The estimates of return flow can be used by water-management agencies in determining return-flow credits for the States of Arizona and California.

From introduction: The intent of this study was to develop a method of estimating overall self-supplied industrial water requirements using coefficients of water use for production and employment from five major-use industrial categories. Those categories included food and kindred products, lumber, pulp and paper, chemical and allied products, and petroleum industries.

From purpose and scope: The purpose of this part of the Central Valley Aquifer Project is to gather and analyze all available information on the magnitude and distribution of ground-water pumpage in the Central Valley. These data will be used as input to a digital ground-water model, one of the products of the Central Valley Aquifer Project.