Travis,
While I’ve moved to New Mexico, I continue for the time being to maintain the TSS files for Kendall County (as well as Bexar and Comal). No cave in the files is reported to extend under the Guadalupe River. Can you or Joe Ranzau (who I know is neck-deep in wedding preparations and other matters) send me more information on the cave you mentioned below. Are you sure it wasn’t Cricket Cave, which is north of CWAN and on CWAN property? If the cave is in the database, I’ll get you more information on it. If it is new to the database, then Texas is officially one cave richer. On the question of air-filled caves extending under rivers, the potential for it depends on the elevation of the water table. Generally speaking, a river is the surface expression and extension of the groundwater table. By definition, all spaces below the water table are filled with water. The Guadalupe River is one such stream and so no air-filled caves should exist below it. However, many streams have “losing” reaches where the water table is below the stream bed and the streams lose their flow the further they extend over such areas, often going completely dry. Most of the streams that extend across the Edwards Aquifer Recharge Zone are losing streams and places where you can find caves below stream beds. I can think of several examples. While karst aquifers are known to rapidly transmit water underground, they are also good at perching water for short distances (relative to the overall scheme of things). These aquifers are triple permeability (the measure of how fast water flows through rock or soil) systems. The bedrock or matrix permeability transmits water at rates of meters per thousands of years and provides the bulk surface on which losing streams flow. Significant water loss in losing streams occurs in fracture permeability, where groundwater may be months or decades old, and in conduit permeability. Hydrologically, conduits are generally any continuous cavity more than about 15 mm in diameter or width. Caves are just big conduits that people can enter. In terms of how water flows, its chemistry, ability to transport sediment and provide habitat to critters, and vulnerability to contamination, conduits and caves are largely indistinguishable. And I don’t think I need to describe to cavers how fast water can move in caves. George From: [email protected] [mailto:[email protected]] Sent: Friday, July 11, 2008 11:50 AM To: [email protected] Subject: RE: [Texascavers] RE: Explore a cave? I seem to recall going into a cave north of CWAN back in the day, maybe it was called Chimney Cave or something? It was in a definite karst area (no soil) and had a ladder going down into the entrance pit. Beyond the entrance room, it was a series of stoop walking passages with places to stand up here and there. Anyways, I was told it went directly under the Guadalupe River near it's terminus, but I have no idea if that is true.. There were mostly SA folks (I can remember Ranzau being there as a mere high school senior just getting his feet wet in the caving world), Spencer Woods and Amanda and I. Anyways, was this ever confirmed by a survey? TS (I think I even took a video camera and recorded the cave from entrance to near the end, need to find that..) I also remember coming out of the cave one night late and becoming COMPLETELY lost with fading lights and no batteries. About the time we resolved to just sleep on the ground, we stumbled onto the trail. We slept good in the owners spare quarters with the heater that night. Actually, there are a number of caves in various places where you can walk or crawl under active flowing streams. Blackhouse Mountain Cave in Tennessee is a great example as one of the passages in this multi-mile long cave goes completely under a flowing stream and has an entrance on both sides of the creek. Geary
