Seminole Canyon is known for being hot and dry. That dry desert environment leads to wonderful preservation of rock art and delicate artifacts such as basketry, sandals and twisted cordage. But occasionally Mother Nature creates conditions for beautiful rain in this dry land. And sometimes it is just too much of a good thing.
The weekend of September 20, 2013 saw such conditions arise as a cold front moved down from the north
to hit warm tropical moisture from the southwest from Hurricane Manuel, which did considerable damage in Acapulco. That combination can create the “perfect storm” in the Chihuahuan Desert. In the three days from September 19 to 21, 2013, Seminole Canyon State Park had over five inches of rain, and the weather station Langtry 10.6 W (elevation 1623) on http://www.theweathercollector.com registered 4.47 inches. In a region that generally only receives 18 inches or less of rain per year, that’s a lot.
Perhaps more importantly, upstream of Seminole Canyon, areas received from 6 to almost 8 inches of rain in the same period. This created massive run-off, that eventually drained into the canyons. In addition, the Rio Grande rose quickly, backing more water up into canyons. Just notice which way the water is rushing in the big picture above.
Fortunately, no damage was done to major rock art, that I know of, since the water did not get that high. But tours to Fate Bell Shelter were shut down for several days.
It rained hard the night of July 3, 2010 as well, again due to a stalled out tropical system.
Pour-offs in Mile Canyon, in Langtry, Texas, home of the famous Bonfire Shelter bison jump, rushed with brown, frothing water. The Rio Grande also rose, backing up in the short canyon and creating very dangerous conditions for wildlife, humans, and ancient debris.
The worst flood in the region in recorded history occurred in 1954, when a hurricane stalled out over the area. More than 20 inches of rain fell in one night over Mile Canyon. The ground was already saturated from an 8-inch rain a few days before, so the water had no place to go. Catastrophic floods like this occur once or twice a century and cause changes topography of the canyonlands. As the website Texas Beyond History (http://www.texasbeyondhistory.net) says, “Spring-fed pools become choked with gravels, new springs emerge, and walnut trees are ripped out.” This flood also moved boulders as large as a small house at least a quarter mile downstream, and damaged rock art in Eagle Cave. We can only image the artifacts that washed away, never to be seen again.