Describes regulatory boundaries of Edwards Aquifer Recharge Zone based on the adoption of the Texas Commission on Environmental Quality (TCEQ) Recharge Zone Boundary, defined in September of 2005.

Publication_Date: 20050901 Title: Edwards Aquifer Protection Program, Chapter 213 Rules - Recharge Zone, Transition Zone, Contributing Zone, and Contributing Zone Within the Transition Zone. This dataset represents the geographic areas identified in TCEQ rules as being subject to regulation under the Edwards Aquifer Protection Program. The coverage was derived from existing official hard copy maps, containing regulatory boundaries based on previous geologic interpretation of the Edwards Aquifer Recharge, Transition, Contributing and Contributing Within the Transition zones, as defined in 30 TAC 213. This dataset contains lines, area features and zone types attributes extended to all 90 USGS 7.5-minute maps under TCEQ rules. Effective September 1, 2005, amended 30 TAC 213 changes the designation of portions of four areas in northern Hays and southern Travis Counties. The commission adopts changes from transition zone to contributing zone within the transition zone, from transition zone to recharge zone and from recharge zone to transition zone. These changes were made to regulatory zone boundaries on the Oak Hill 7.5 Minute Quadrangle, the Mountain City 7.5 Minute Quadrangle, and the Buda 7.5 Minute Quadrangle. Also effective September 1, 2005, with this amendment, the commission is adopting changes from transition zone to recharge zone, and contributing zone within the transition zone; in southern Hays and Comal Counties for areas along the eastern boundary of the recharge zone in the vicinity of the Blanco River, the City of San Marcos, the City of New Braunfels, the community of Hunter and the community of Garden Ridge. Changes are depicted on the Mountain City 7.5 Minute Quadrangle; on the San Marcos North 7.5 Minute Quadrangle; on the San Marcos South 7.5 Minute Quadrangle; on the Hunter 7.5 Minute Quadrangle; and on the Bat Cave 7.5 Minute Quadrangle. The commission also adopted changes along the western boundary of the recharge zone in southern Hays and Comal Counties. Effective September 1, 2005, areas are changed from contributing zone to recharge zone in the Guadalupe River basin, and other areas in the Guadalupe River basin, and near Wimberley are changed from recharge zone to contributing zone. These changes occur on the Smithson Valley, Sattler, Devil’s Backbone and Wimberley 7.5 Minute Quadrangles. Another area near Hays City was changed to recharge zone from contributing zone, and is changed accordingly in the Driftwood 7.5 Minute Quadrangle. Purpose: This dataset provides TCEQ regional office and public with information on Edwards Aquifer Protection areas and types, including changes made to the boundaries by the most recent rules revisions, according to 30 TAC Ch. 213 (1999). This coverage is to facilitate the eventual replacement of the hard copy maps, historically used to identify the geographic location of Edwards Aquifer Protection Program regulated areas. The purpose of the TCEQ Rule 30, Texas Administrative Code(TAC), Chapter 213 is to regulate activities having the potential for polluting the Edwards Aquifer and hydrologically connected surface streams in order to protect existing and potential uses of ground- water and maintain Texas Surface Water Quality Standards. The following definitions are founded under Chapter: The Edwards Aquifer - portion of an arcuate belt of porous, waterbearing, predominantly carbonate rocks known as the Edwards (Balcones Fault Zone) Aquifer trending from west to east to north- east in Kinney, Uvalde, Medina, Bexar, Comal, Hays, Travis, and Williamson Counties; and is composed of the Salmon Peak Limestone, McKnight Formation, West Nueces Formation, Devil's River Limestone, Person Formation, Kainer Formation, Edwards Group and Georgetown Formation. The permeable aquifer units generally overlie the less- permeable Glen Rose Formation to the south, overlie the less- permeable Comanche Peak and Walnut formations north of the Colorado River, and underlie the less-permeable Del Rio Clay regionally. (30 TAC, § 213.3(8) ) Recharge Zone - area where the stratigraphic units constituting the Edwards Aquifer crop out, including the outcrops of geologic form- ations in proximity to the Edwards Aquifer where caves, sinkholes, faults, fractures, or other permeable features would create a potential for recharge to surface waters into the Edwards Aquifer. (30 TAC, § 213.3(25) ) Transition Zone - area where geologic formations crop out in proximity to and south and southeast of the recharge zone and where faults, fractures, and other geologic features present a possible avenue for recharge of surface water to the Edwards Aquifer, including portions of the Del Rio Clay, Buda Limestone, Eagle Ford Group, Austin Chalk, Pecan Gap Chalk, and Anacacho Limestone. ( 30 TAC, § 213.3(34) ) Contributing Zone - The area or watershed where runoff from precipitation flows downgradient to the recharge zone of the Edwards Aquifer. The Contributing Zone is located upstream (upgradient) and generally north and northwest of the Recharge Zone for the following counties: (A) all areas within Kinney County, except the area within the watershed draining to Segment 2304 of the Rio Grande Basin; (B) all areas within Uvalde, Medina, Bexar, and Comal Counties; (C) all areas within Hays and Travis Counties, except the area within the watersheds draining to the Colorado River above a point 1.3 miles upstream from Tom Miller Dam, Lake Austin at the confluence of Barrow Brook Cove, Segment 1403 of the Colorado River Basin; and (D) all areas within Williamson County, except the area within the watersheds draining to the Lampasas River above the dam at Stillhouse Hollow reservoir, Segment 1216 of the Brazos River Basin. ( 30 TAC, §213.22(2) )
Contributing Zone Within the Transition Zone - The area or watershed where runoff from precipitation flows downgradient to the Recharge Zone of the Edwards Aquifer. The Contributing Zone Within the Transition Zone is located downstream (downgradient) and generally south and southeast of the Recharge Zone and includes specifically those areas where stratigraphic units not included in the Edwards Aquifer crop out at topographically higher elevations and drain to stream courses where stratigraphic units of the Edwards Aquifer crop out and are mapped as Recharge Zone. ( 30 TAC, § 213.22(3) )

Publication_Date: 20050901 Title: Edwards Aquifer Protection Program, Chapter 213 Rules - Recharge Zone, Transition Zone, Contributing Zone, and Contributing Zone Within the Transition Zone. This dataset represents the geographic areas identified in TCEQ rules as being subject to regulation under the Edwards Aquifer Protection Program. The coverage was derived from existing official hard copy maps, containing regulatory boundaries based on previous geologic interpretation of the Edwards Aquifer Recharge, Transition, Contributing and Contributing Within the Transition zones, as defined in 30 TAC 213. This dataset contains lines, area features and zone types attributes extended to all 90 USGS 7.5-minute maps under TCEQ rules. Effective September 1, 2005, amended 30 TAC 213 changes the designation of portions of four areas in northern Hays and southern Travis Counties. The commission adopts changes from transition zone to contributing zone within the transition zone, from transition zone to recharge zone and from recharge zone to transition zone. These changes were made to regulatory zone boundaries on the Oak Hill 7.5 Minute Quadrangle, the Mountain City 7.5 Minute Quadrangle, and the Buda 7.5 Minute Quadrangle. Also effective September 1, 2005, with this amendment, the commission is adopting changes from transition zone to recharge zone, and contributing zone within the transition zone; in southern Hays and Comal Counties for areas along the eastern boundary of the recharge zone in the vicinity of the Blanco River, the City of San Marcos, the City of New Braunfels, the community of Hunter and the community of Garden Ridge. Changes are depicted on the Mountain City 7.5 Minute Quadrangle; on the San Marcos North 7.5 Minute Quadrangle; on the San Marcos South 7.5 Minute Quadrangle; on the Hunter 7.5 Minute Quadrangle; and on the Bat Cave 7.5 Minute Quadrangle. The commission also adopted changes along the western boundary of the recharge zone in southern Hays and Comal Counties. Effective September 1, 2005, areas are changed from contributing zone to recharge zone in the Guadalupe River basin, and other areas in the Guadalupe River basin, and near Wimberley are changed from recharge zone to contributing zone. These changes occur on the Smithson Valley, Sattler, Devil’s Backbone and Wimberley 7.5 Minute Quadrangles. Another area near Hays City was changed to recharge zone from contributing zone, and is changed accordingly in the Driftwood 7.5 Minute Quadrangle. Purpose: This dataset provides TCEQ regional office and public with information on Edwards Aquifer Protection areas and types, including changes made to the boundaries by the most recent rules revisions, according to 30 TAC Ch. 213 (1999). This coverage is to facilitate the eventual replacement of the hard copy maps, historically used to identify the geographic location of Edwards Aquifer Protection Program regulated areas. The purpose of the TCEQ Rule 30, Texas Administrative Code(TAC), Chapter 213 is to regulate activities having the potential for polluting the Edwards Aquifer and hydrologically connected surface streams in order to protect existing and potential uses of ground- water and maintain Texas Surface Water Quality Standards. The following definitions are founded under Chapter: The Edwards Aquifer - portion of an arcuate belt of porous, waterbearing, predominantly carbonate rocks known as the Edwards (Balcones Fault Zone) Aquifer trending from west to east to north- east in Kinney, Uvalde, Medina, Bexar, Comal, Hays, Travis, and Williamson Counties; and is composed of the Salmon Peak Limestone, McKnight Formation, West Nueces Formation, Devil's River Limestone, Person Formation, Kainer Formation, Edwards Group and Georgetown Formation. The permeable aquifer units generally overlie the less- permeable Glen Rose Formation to the south, overlie the less- permeable Comanche Peak and Walnut formations north of the Colorado River, and underlie the less-permeable Del Rio Clay regionally. (30 TAC, § 213.3(8) ) Recharge Zone - area where the stratigraphic units constituting the Edwards Aquifer crop out, including the outcrops of geologic form- ations in proximity to the Edwards Aquifer where caves, sinkholes, faults, fractures, or other permeable features would create a potential for recharge to surface waters into the Edwards Aquifer. (30 TAC, § 213.3(25) ) Transition Zone - area where geologic formations crop out in proximity to and south and southeast of the recharge zone and where faults, fractures, and other geologic features present a possible avenue for recharge of surface water to the Edwards Aquifer, including portions of the Del Rio Clay, Buda Limestone, Eagle Ford Group, Austin Chalk, Pecan Gap Chalk, and Anacacho Limestone. ( 30 TAC, § 213.3(34) ) Contributing Zone - The area or watershed where runoff from precipitation flows downgradient to the recharge zone of the Edwards Aquifer. The Contributing Zone is located upstream (upgradient) and generally north and northwest of the Recharge Zone for the following counties: (A) all areas within Kinney County, except the area within the watershed draining to Segment 2304 of the Rio Grande Basin; (B) all areas within Uvalde, Medina, Bexar, and Comal Counties; (C) all areas within Hays and Travis Counties, except the area within the watersheds draining to the Colorado River above a point 1.3 miles upstream from Tom Miller Dam, Lake Austin at the confluence of Barrow Brook Cove, Segment 1403 of the Colorado River Basin; and (D) all areas within Williamson County, except the area within the watersheds draining to the Lampasas River above the dam at Stillhouse Hollow reservoir, Segment 1216 of the Brazos River Basin. ( 30 TAC, §213.22(2) )
Contributing Zone Within the Transition Zone - The area or watershed where runoff from precipitation flows downgradient to the Recharge Zone of the Edwards Aquifer. The Contributing Zone Within the Transition Zone is located downstream (downgradient) and generally south and southeast of the Recharge Zone and includes specifically those areas where stratigraphic units not included in the Edwards Aquifer crop out at topographically higher elevations and drain to stream courses where stratigraphic units of the Edwards Aquifer crop out and are mapped as Recharge Zone. ( 30 TAC, § 213.22(3) )

This layer represents the boundaires of watersheds which have a contributing impact on the Edwards Aquifer.The Edwards Aquifer contributing zones polygon file was created from modeled boundaries (2003 LIDAR) and customized boundaries based on contours, drainage infrastructure, COA Plans, and staff knowlege.