Pajaro Valley is a simulation data set for use with the three-dimensional finite difference ground-water flow model MODFLOW by McDonald and Harbaugh (USGS, 1988). The data set represents a three-layer mathematical model of the Pajaro Valley Aquifer System, California, developed by Mitten and Londquist (USGS, 1990). The modeling was performed as part of a hydrogeologic study as reported by Johnson et al. (USGS, 1988). The description of the construction of the regional model and its use in characterization of water resources management options, together with the complete model input files provides an excellent opportunity to become familiar with the MODFLOW model and to understand its application to intermediate-scale water resources studies.
Pajaro Valley is a 160 square miles area located in southern Santa Cruz and northern Monterey Counties. It consists of alluvial bottom lands, terraces and foothills. The hydrogeologic system is bounded by drainage divides, the Santa Cruz Mountains, and the Monterey Submarine Canyon in Monterey Bay. The model area is a 10 by 8 mile section of the valley, sloping gently westwards from the mountains to the coast. The Pajaro river flows westwards through the study area. The hydrogeologic system is characterized by three unconsolidated rock aquifers separated by discontinuous confining layers of clay and silty clay. The upper aquifer is unconfined.
This data set contains ready-to-use MODFLOW input and output files and includes hard copies of the data set documentation by Mitten and Londquist (1990) and the Water-Resources Investigations Report by Johnson et al. (1988). The data set is distributed by IGWMC, requiring 1.1 Mb disk space to down load. Note that the MODFLOW software is not included.