 Building ecosystems has little to do with building office towers or highway systems. Think about it. While it may take a decade to build a major expressway loop around Dallas or Houston or San Antonio, imagine how long it took for Nature to carve out the Grand Canyon. Miracles don't happen overnight!
Or do they?
Nature, it seems, is a strange and sometimes unpredictable thing, and recently formed Canyon Lake Gorge in Central Texas is evidence to the fact.
In July of 2002 Nature released a watery deluge on the hills and valleys that surround manmade Canyon Lake. The rains were hard and many and lake levels rose steadily in spite of open flood gates on Canyon Dam. A well designed and never used spillway served its purpose. Lake waters crested the spillway as designed and within 48 hours Nature demonstrated its destructive and creative powers both at the same time.
Below the spillway -- up until the afternoon of July 4, 2002 -- stood a valley covered in mesquite and oak trees. It sat behind the spillway that was built as a safety valve for Canyon Lake, a popular recreation spot in the Texas Hill Country between San Antonio and Austin.
The torrent of flood waters stripped the valley of all soil and vegetation, exposing rock formations, fossils and even dinosaur footprints. Since then, the canyon has been accessible only to researchers to protect it from vandals, but in October it opened to its first public tour.
According to the Fish and Wildlife Service, ecosystems can be as small as a
backyard pond or as large as the Earth. They could have been created when
dinosaurs roamed or as recent as three years ago.
 "It exposed these rocks so quickly and it dug so deeply, there wasn't a blade of grass or a layer of algae," said Bill Ward, a retired geology professor from the University of New Orleans who started cataloging the gorge almost immediately after the flood.
In the wake of the tremendous loss from the heavy rains which filled the
Guadalupe River watershed, allowing the lake to flow over its uncontrolled
spillway, the one-mile gorge was carved into the limestone. Roaring down the
spillway at a peak flow of just under 70,000 cubic feet of water per second, the
water carved a gorge hundreds of yards wide and 50 or more feet deep back one mile to the Guadalupe River channel.
Researchers immediately closed the area to protect the uncovered limestone gorge and the new ecosystem it represented. But a cooperative agreement between the U.S. Army Corp of Engineers and the Guadalupe-Blanco River Authority, the protected area is being opened on a limited basis to the public and plans are underway to construct walk trails and observation points along the gorge when visitors can view the natural wonder without disturbing the fragile limestone.
Dr. Carter Keairns, Texas State University, geologist and Dr. Bill Ward, a retired geologist on the Citizens Board and the Gorge Scientific Committee, served as guides for the first tour. Keairns pointed out fossils, dinosaur tracks and even a fault line that was exposed by the raging water.
“The three-toed prints were probably made by a theropod dinosaur,” said Keairns. “The theropod, walking on hind legs with a stride of about nine feet, was perhaps 30 feet in length. These tracks are similar to the ones found in Glen Rose, Texas, which shows that there was a dinosaur presence in the state."
Individuals wanting to tour the gorge need to contact the Guadalupe-Blanco River Authority. The Guadalupe Blanco River Authority, which has a lease from the Army Corps of Engineers to manage the 64-acre Canyon Lake Gorge site, will begin offering limited public tours of the canyon Saturday, continuing year-round on the first Saturday of the month.
Early demand for the 3-hour tours is so high they are booked for at least six months. Rhoad said the authority hopes to train more docents so dates can be added.
Visitors will not be allowed to hike the canyon on their own because the brittle limestone is still breaking from the canyon walls.
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