The Upper Guadalupe

This is the Guadalupe River, and everything passing under the bridge is about ten miles from the end of its free-flowing life. Downstream the valley opens into Canyon Lake, impounded by the Army Corps of Engineers in 1964 for flood control on a river that had repeatedly wrecked New Braunfels and Seguin. Above the dam the Guadalupe still behaves like a Hill Country stream: clear green water over limestone, deep pools between gravel bars, bald cypress rooted in the streambed, and a flow that can climb from a few dozen cubic feet a second to tens of thousands in a night. The Guadalupe runs some 230 miles from springs in western Kerr County to San Antonio Bay, and this stretch above the lake is the part that still looks like its beginning. In the summer of 2002 more than thirty inches of rain fell across the basin. Canyon Lake rose over its emergency spillway for the first time since the dam was built, and the overflow cut a gorge more than a mile long through the limestone in roughly six weeks. It stripped off the soft rock to expose dinosaur tracks and a fault that had not seen daylight since it formed. Geologists were able to watch a canyon form on a human timescale, which almost never happens. Below the dam the water released from deep in the reservoir comes out cold all year round. That accident of engineering supports the only year-round trout fishery in Texas, stocked continuously since 1966.