Res 1994-166 - Laserfiche WebLink

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'5ZJ area. Within the recharge area, groundwater generally 1S under unconfmed conditions . Recharge to the Aquifer occurs in the outcrop area, primarily from streams crossing over the upper portion of the Nueces River Basin, the upper portion of the San Antonio River Basin and a part of the upper portion of the Guadalupe River Basin. Water readily infiltrates the highly fractured and permeable carbonate rocks that occur along the streambeds, and through karstic features such as sinkholes. . Water movement IS generally in a west to east direction, however, due to complex structural faulting and stratigraphic heterogeneity, Aquifer compartmentalization is likely and local flow paths are undefIned. The Knippa Gap (the "Gap"), located near the Uvalde and Medina County line, is a partial barrier (constriction) to flow, from west to east, within the Aquifer because of yet undefmed, suuctural and stratigraphic variations in the rock. As_a result, the restriction to transmissivity of water, can create a reservoir pressure differential on either side of the Gap. The effect can be evidenced at certain times by higher water levels in wells on the Uvalde side of the Gap. Groundwater discharge from the Aquifer in the region is by springflow and by either flowing or pumped discharge from wells. The very high yield ,of the artesian wells result from the intersection of permeable, vugular stratum by the well bore. The'depths to those strata vary with location and depend on the topography and the structural configuration of the Aquifer. These depths range from less than 100 feet within the unconfined Aquifer to more than 3,000 feet in the confined Aquifer. Water production from the artesian zone of the Aquifer supportS municipal, industrial, commercial and agricultural uses for over a million people, Six major springs are natural outlets of the Aquifer. In Comal and Hays Counties, major discharge points for ~e freshwater zoned occur at Cornal Springs and San Marcos Springs, respectively. Water flow from the springs supportS commercial, industrial, municipal uses and several endangered species. 5.2. Lon~-term Plannin~. The Parties agree to collect information on current usage patterns to project future needs and ensure adequate long-term water supplies. The Parties further agree to adopt policy or rules requiring accurate reporting of ~ production from all wells located within each District. Cumulative use from domestic and livestock wells producing less than 25,000 gallons per day shall be estimated by the Districts utilizing USGS fIgures. 5.3. Sprin~flow. The Parties agree to enact water use policies to maintain springflows at levels adequate to comply with the Endangered Species Act. Accordingly. the Parties agree to take all steps required by existing law to ensure compliance with the Endangered Species Act. - 6 -