By Kayleen Holder
MEDINA COUNTY–When landowners stumbled upon a hidden sink hole with a small hole on the Seco Valley Ranch north of Hondo, they dropped a rock inside, “and it took a long time to hit bottom.” They knew then they had found something special, but had no idea just how truly extraordinary it would be. A neighbor who had grown up exploring the ranch knew of at least one sink hole on the property, the Davis family said, so they called out the local grotto. Little did he know as a young boy, there truly was a treasure beneath the surface of the family ranch.
“Located only a few hundred yards from our foreman’s residence, this sinkhole was concealed in a brushy area no-one had ever explored due to the rocky terrain,” said landowners Mr. and Mrs. Don and Debbie Davis. “We knew of one (other) large sinkhole on the property that our neighbor Randy Rugh told us about many years ago. Randy is the great-nephew of the previous landowner and grew up exploring the entire property.”
Last Monday, August 22, two lucky cave explorers went inside and discovered the massive underground room, measuring about 130 tall x 70 feet around. Cave explorer, Bennett Lee was the first one in the hole, along with fellow explorer Matthew Taylor.
This was certainly a day to remember for Lee, who is a computer tech man by day and a “caver” just for fun.
“There are only a few caves in Texas with a room this big. It’s really rare to find a room and formations this big,” Lee said. “As a caver, you go to hundreds of sites and stick your head in, and most of the time, almost always, it’s nothing. This is one we are all looking for!”
Lee has been exploring caves since the 80s and has seen a lot over the years, and he notes that any possible connecting caves could be even more remarkable.
“The underground world is something that most people will never see. It’s like the last frontier,” Bennett said. “Every mountain top, every stream, someone has walked it, but these underground caves have been sealed up for hundreds of thousands of years. It’s like walking on the moon. We know we are the first people to ever set foot down there,” Lee said.
“It is hundreds of thousands of years old,” he said, and there are impressive formations all over the walls of the cave.
“The two main formations in there dwarf the others,” Bennett said. “One was about 30 feet high, and then there are two stalagmites that grew together about halfway up, and those are about 20 feet. The photo was taken on the uphill side, so it does not show the full height. Formations this large take a very long time to form.”
Another unique feature is what he calls a “broomstick column” which is formed by a stalagmite and a stalactite which grew together from above and below.
He spoke a little about how sink holes form.
“Usually what happens is the ceiling of a cave collapses, slowly over time. Over hundreds of thousands of years, little pieces of rock fall from the ceiling, one after another, into this now huge cavern underground. The rock above the cave becomes weak and as it erodes and falls, eventually, you start to see this sink hole form on the surface,” Lee said. “Exploring caves is a very fun, exciting, and dangerous business!”
In this stunning underground room, named Woot Cavern, explorers will search for a connecting cave, which could be even more marvelous than the initial discovery. Lee has worked on a project near Leakey, for example, where cavers found a cave spanning over six miles long, underground, with no end in sight.
“With a room this size, there was obviously something there at one time,” Lee said. “We just have no idea what to expect. We have to go back down there and poke around, see if we can find a connecting cave and get past the breakdown. There are several large boulders. We may never get past the break down,” Lee said.
The 1,883-acre ranch in northeast Medina County has several sink holes, but nothing like this one.
When you are looking for a sink hole, you might look for “a circular depression about 10-30 feet in diameter, that’s about 6 feet lower than the ground around it,” Lee said. “Sometimes smaller, sometimes only 2 feet deep.”
“Winter time is a great time to walk the ranch. If you see any steam coming up from the ground, that’s a huge sign. Or after a huge rain, water might run down into a sink hole. Sink holes are important recharge zones for the aquifer.”
If you suspect you see a sinkhole on your land, you can contact the Bexar Grotto team, and they will come check it out for free.
Limestone is typical of caves and Texas is covered with limestone. From San Antonio to Austin, sink holes are actually very common, he says. The Grotto group does what’s called “karst walks”, where we have a line of people and walk across the land looking for signs
“There’s a lot of caves around here, especially around the Hill Country area,” Lee said. “It’s just a matter of finding them.”
Q&A with the Davis family at Seco Valley Ranch:
How did ya’ll first see it?
Last February, we invited members of Bexar Grotto, a non-profit caving group, to explore the cave associated with the sinkhole about which we knew. They opened up passages enough for people to crawl in and discovered a large room with ancient stalagmites and stalactites (remember your school mnemonic; Stalactites hold tightly to the ceiling and Stalagmites might make it to the ceiling someday). The Hydrologist with this group explained to us this sinkhole and others in the area were springs in the Paleolithic Era where aquifer waters were forced upwards and fed the shallow sea that covered this area. These openings now serve to direct rainfall down into the aquifer. YouTube video with images of this karst feature. https://youtu.be/t1556eJzKow
Prior to initiating exploration of that karst, we named DWD Grotto, our ranch foreman Jaime Sanchez discovered a second sinkhole while clearing juniper brush. We still plan to excavate this cave that is located near a wet weather creek. https://youtu.be/B0XAGk0pgN0
The EAA uses precise satellite hill shade maps to identify depressions on the land surface. They located two more areas of interest. The third turned out to contain the small opening to this spectacular cavern. We invited Bexar Grotto out again. Bennett Lee and Matthew Taylor rappelled 80’ down from the tiny entrance and discovered a huge open room with a spectacular column of glistening flowstone and a second tower. https://youtu.be/kYWKgqm_rfU
Our ranch is located along the Balcones Escarpment, an area known for its high aquifer recharge ability due to fracturing from the ancient Balcones Fault line. The aquifer supplies water to the city of San Antonio, among others. Due to climate change and increased urban water needs, the Edwards Aquifer Authority is actively seeking private lands to enroll in conservation easements, a program that pays landowners a percentage of the current land value to restrict development in perpetuity.
We decided along with several of our neighbors, to conserve this significant area. As part of the research conducted by EAA, a team of Geologists and Hydrologists work in cooperation with Biologists with Green Spaces Alliance, a 501(C)3, to survey the properties, mapping noteworthy features.
How many sink holes have ya’ll found in all? 4
What did ya’ll do when ya’ll first found the hole?
While shining a light down the small opening, we could see there was a floor. Tossing in a rock was our first attempt to determine the depth of the cavern. It took 3 ½ seconds to hit the bottom. Next, I tied a cord to a rock and lowered it, so I could measure the length of cord. I measured roughly 70 feet.
Did ya’ll imagine it was going to be anything like it turned out to be?
Heavens no! We could tell the room opened up after the tiny entrance, but could only see darkness. We never dreamed this would be larger than the first karst we explored.
How long have ya’ll lived there? 23 years
Please share any ranch history or interesting stories?
We are about 2 miles northeast of the large Valdina Sinkhole on the Seco Creek. There are numerous caves in this area. This ranch was pieced together in the 1930’s by Charlie Rugh. He left the property to his two nephews that divided the ranch. We purchased half from one brother and our neighbor Randy and his brother inherited their side from their parents Ronnie and Carolyn. Charlie was a sheep and goat farmer. His nephews leased the grazing for cattle and goats. When we took over management, we converted to a cattle operation where we produce grass-fed beef on a small scale for sale to end users.
What is it like–knowing there could be a massive cave running underground across your ranch from this site?
Very, very exciting. We are conservation ranchers. We manage our grazing holistically to sustain soil health while raising a Critically Endangered breed. In a drought year such as this one and the previous two, it is hard to regenerate the soils, but we do our part not to cause damage to soil health and maintain groundwater retention.
We already were making plans to create some kind of land trust, so when we are gone, a living herd of conservation genetics Texas Longhorns will be perpetuated for public appreciation, education and scientific research. The Texas Longhorn is the only breed that evolved in this region by natural selection. They are uniquely adapted to thrive in this environment and promise to be of economic importance to the future of our nation’s food supply as our climate changes. Although there are tens of thousands of horned cattle in this country, only perhaps 3000-3500 animals possess Iberian-descent genetics not mixed with other breeds. These are the cattle we raise. Protecting and developing these karst features for the same public use falls right into our conservation goals. Our ranching operation is also Audubon Certified Bird Friendly Land. This area is sanctuary for endangered Golden-cheeked Warblers and many colorful songbirds.
We do not have any children to inherit our property, so our focus is conservation for the public good.
By Kayleen Holder