From Wikipedia:
“A flash flood is a rapid flooding of geomorphic low-lying areas: washes, rivers, dry lakes and basins. It may be caused by heavy rain associated with a severe thunderstorm, hurricane, tropical storm, or melt water from ice or snow flowing over ice sheets or snowfields. Flash floods may occur after the collapse of a natural ice or debris dam, or a human structure such as a man-made dam, as occurred before the Johnstown Flood of 1889. Flash floods are distinguished from a regular flood by a timescale of less than six hours. The temporary availability of water is often utilized by foliage with rapid germination and short growth cycle, and by specially adapted animal life.”
One day a week, Laura and I have a ‘project day.’ This is a day for us to go out, explore the park, volunteer for other park programs, and the like. The project day is in addition to our 3 days to run the visitor center. In addition to hiking trails, the park has an extensive network of dirt roads, some are maintained for all vehicles, and some are ‘backcountry dirt roads’ which require high clearance and 4 wheel drive vehicles. Often on our project days we use a park vehicle that is both high clearance and 4 wheel drive to explore these interesting and remote parts of the park.
Well this week, despite a bit of rain the night before, we planned to drive the Old Ore Road. This is a back country dirt road that is 26 miles long and traverses the eastern part of the park. We had driven this road once before, but afterwards learned about a tenaja that we had missed and wanted to check out. (A tenaja is a natural formation that occurs from eroding water in limestone rock surfaces – it is like a large, smooth-sided bowl that collects water, anywhere from 5 feet to 25 feet across or more.) So, we looked at the skies, partly cloudy with a bit of rain falling off in distance in the east, and headed out on the road.
The first 7 miles or so were uneventful, if you call 4 wheel driving in the high desert uneventful, until we crested a high point on the road that led down to a wash at the base of some high cliffs that had waterfalls flowing from the recent rain.
At this point, the road which had been in pretty good condition, got kind of bad as we went down the hill. And, at the bottom of the hill, we saw a rather large raging river cutting directly across and then following the road for a ways. So, we parked the truck and walked down the hill to scout out the situation and our options.
As you can see from the picture below, the dry wash that we needed to cross was no longer a dry wash, but a flash flood. (All of this water resulted from a couple of hours of rain that measured about .75 inches!)
We had three options – turn around, go forward, or wait. Turning around was not too exciting – we had been there already, it would put us further away from our final destination, and there was of course the chance that flash floods had developed behind us – it looked like rain had started to fall behind us. We, as you know, are new at this desert life (anybody catch the unintended reference to a Counting Crows album title?) and so the option of just driving into the raging water (even though it didn’t look that deep) was not appealing either. So, we decided to wait and see how long the flood would ‘flash.’
We put a rock on the edge of the water to try to measure and get a sense of how quickly the water was receding. The flood looked like it was about a foot and a half or more deep and was about a 100 yards long that we would need to cross. We also threw a few large rocks into the middle to get a sense of the current. Based on our observations, it seemed if we waited for a while, the water would be passable. Which after about 40 minutes it appeared to be.
Of course, as soon as we crossed and got to dry land and turned a corner and were confronted with a larger and quicker flood once again in front of us! I stopped the truck to get out and scout this crossing, when, and you can’t make this stuff up, I noticed we had a flat!
So, while we changed the flat, in the mud and rocks I might add, the water level for this new flood crossing went down enough for us to once again safely pass. Which we did. As we drove across we were happy to see that the road began to rise out of the low point, climb up the hills, and away from these floods.
But there is more! After a few more miles, we started to go down again and turned into a narrow box canyon. And guess what, the road veered not only into the narrow end of the canyon, but of course went nearly down to the canyon floor! And, right were the road began to turn out of the canyon and regain elevation was the fastest and most violent flash flood we had seen yet! It wasn’t very wide, maybe 40 feet, but it was raging and looked deep.
Once again we scouted the crossing, weighed our options, and decided to hang out a bit and wait. But, since we saw possible rain clouds to our north and east, we weren’t going to wait too long in case things got any worse. So, as soon as we estimated the water was passable, we inched the truck into the water and then moved through at a steady pace till we made it to the other side.
Well, since you are reading this, we clearly made it through and back to Panther Junction, not that there was any doubt! We had another 14 miles or so left of the road, and as is common in the desert, the rest of the road was completely dry. It appeared that no rain had fallen south of the box canyon that we had just navigated through. Overall, it was a bit of a harrowing experience, a learning experience, a challenging experience, and ultimately, another great new experience to add our adventures here in Big Bend.
Postscript: When we got back to Panther Junction, we reported our flat. We were told to bring the flat tire to the auto shop to be repaired. But we were also told, not to hold our breath. The park currently does not have a mechanic on staff! One retired 2 weeks ago and the other is on a detail in another park for the summer! Anybody know how to fix a flat?
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