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USGS · ofr81139

Evaluation of ground-water monitoring network, Santa Cruz County, California

G. G. Blankenbaker·Christopher D. Farrar
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Abstract

The Santa Cruz County Flood Control and Water Conservation District seeks to improve the existing network of observation wells to monitor water levels and ground-water quality in the Pajaro Valley subarea and the Aptos-Soquel, San Lorenzo, and Santa Cruz Coastal subbasins in California. The proposed network , consisting of 92 wells, is designed to monitor changes in storage and quality of ground water resulting from climatic changes and management-induced stresses. In the proposed network , water levels in all wells would be measured semiannually, in April and September, and monthly in a few key wells. The water-level measurements would provide data that could be used to determine changes in ground-water storage. In addition to the currently monitored characteristics--temperature, specific conductance, pH, and chloride ion concentration--inclusion of annual sampling and analysis for major ions and nutrients is proposed. The network would also include sampling and analysis for trace elements once every 4 years. More frequent analyses are proposed in areas where water-quality problems are known to exist or where potential water-quality problems are recognized. Analyses for major ions, nutrients, and trace elements are included in the proposed network to provide baseline data for monitoring long-term changes in water quality and to detect any unexpected changes in quality. (USGS)

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G. G. Blankenbaker, Christopher D. Farrar. 1981. Evaluation of ground-water monitoring network, Santa Cruz County, California. https://doi.org/10.3133/ofr81139

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