San Antonio developer plans to seal off cave


Associated Press

Posted on March 23, 2013 at 10:03 AM

SAN ANTONIO (AP) — A subdivision developer who discovered a cave in the San Antonio area has decided to seal off access and will revise its plans so no houses are built above it.

The San Antonio Express-News ( ) reported Friday that the cave was discovered Jan. 30 when a crew was trenching for a sewer line.

The cave has two chambers about 40 feet high and colors in the cave range from bright white and pink to dark red and brown throughout its 450-foot length. Twelve-foot-long stalactites hang from the ceiling and the floor has rounded stalagmites that rise up 15 feet or more.

Officials with McMillin Land Development plan to use a concrete beam and soil to seal off the cave. Already, steel plates have been put over the opening and a chain link fence installed.

Geologist Philip Pearce and his team from Pape-Dawson Engineers last month took four days to map the cave amid growing public attention. Pearce found spelunking gear in the cave and saw some formations had been broken.

McMillin said in a statement that it is proposing to the Texas Commission on Environmental Quality that the planned sewer lines be rerouted so no sewer line will pass over or through the cave. The company also said it is "revising the subdivision plat so that no residential lot will be over the cave."

"We hit voids all the time," said Gene Dawson, president of Pape-Dawson Engineers. "But rarely do we have to redesign a subdivision because of one."

The Edwards Aquifer Authority said the cave is a direct conduit to the Edwards Aquifer, San Antonio's primary water source.

Having the cave closed off is difficult for spelunkers to accept.

Allan Cobb, director of Texas Cave Management Association, said the cave is unique and offers an opportunity to study the geology of the Edwards.

"The formations are what make it interesting," he said, adding they are probably hundreds to thousands of years old.

Cobb would like to see an entrance to the cave left so it could be further explored, monitored and used to teach the public how anything spilled over the recharge zone of the Edwards ends up in the aquifer.

But with the entrance sealed, Cobb knows at least the formations will be protected.


Information from: San Antonio Express-News,