The drought in Texas stretched many years. We worried about the availability of precious, life-giving water, which had once seemed like an inexhaustible gift bubbling out of the hills, even when there wasn’t rain. But as the drought stretched on the ground water depleted more and more, as everyone in communities throughout central Texas took more water out of the aquifer than went in.
The ranch, where my boyfriend, Morgan, was born, is out by the Frio River. Floating the cool, spring-fed river is a great way to spend hundred-degree summer days, but only if there is enough water to carry you in your tube. When the river dries up from a drought, rather than drifting along relaxing, everyone is forced to walk or have their butt dragged along the rocks instead. At the ranch, the lake hadn’t been full in five years and the springs, where water used to pour from the ground, were dry until May 2015, when it rained almost every day and the lake overflowed on the ranch and the Frio went up at least 10 feet in a single day of rain, which moved around logs and cleaned out the debris trapped in the river. Of course, this debris had to go somewhere, so a lake somewhere downstream or the Gulf of Mexico inherited whatever trash the Frio was hiding. Luckily for us, the lake on the ranch is very clean and clear because it is up in the mountains and filled by spring-fed creeks.
The spring water flows up from underground passages that form one of the world’s largest and most prolific aquifers. The Edwards Aquifer stretches west from San Antonio and Austin, providing water for over two million people. Water inside the aquifer can take many year to reach the surface, depending on how fast it travels. In one location tested by scientists, water was four years old on average and some of it was over 300 years old. When surface water in the aquifer’s recharge zone goes underground, it carries pollutants with it that can get trapped in little underground pockets or flow rapidly through larger parts of the network. It all depends on the structure of the limestone. Hydrogeologists use the term matrix to describe a structure where lost of water is stored and the term conduit for places where the water moves through quickly. Water that sits in within the limestone hills for an extended period, dissolves some of the rock. This makes the spring water rich in calcium and carbonate ions, which gives the streams and pools their distinctive blue-green color.
Contrary to popular belief that the limestone and the aquifer are good at filtering water, water that moves through the large pores of the stone conduits quickly doesn’t have a chance to have pollutants filtered out of it. Despite this, the water quality here is exceptional, probably because so much of it went underground before this part of the hill country began being extensively developed for human use. Humans contribute pesticides, herbicides and other pollutants to the watershed, which is particularly dangerous to the aquifer, and everyone’s shared water resource, in the environmentally sensitive recharge zones. In Austin, the city’s Watershed Protection Department works to protect the city’s sensitive water resources with educational programs for children, and signs along the roads that alert driver when they cross the invisible boundaries into different water sheds, especially recharge zone of Austin’s “crown jewel,” Barton Springs.
Even at the ranch, which is at the headwaters of the Frio, we are impacted by the land management decisions made miles away from us in the recharge zone. In the recharge zone south of us in Uvalde county, where most of the land is used for agriculture, when fertilizers and pesticides are applied just before it rains, especially in big “recharge events” like the flood we just experienced, they end up being washed into the aquifer and can travel far from their source to end up in our springs. Texas’s rigid concepts of private property rights, which emphasize an individual’s right to do what they want on their land, dissolve when we are forced to acknowledge the responsibility we have to each other based on our shared water resource, our common ground underground, the Edward’s Aquifer.
After the big rain at the ranch, we went out to sit on a boardwalk that leads to one of the lake’s islands and listened to the frogs croaking. There were many different calls, which I bet meant many species of frog. It is crazy to me to imagine how the frogs must have burrowed into the mud or gone into the springs to survive the drought. Now that the lake is full they seem to be celebrating with their croaking music.
As twilight darkened, the bats began to come out and we watched them fly over the lake, catching millions of insects, while the frogs blasted their croaks across the glass-flat surface of the lake. Their “wub wub” rhythms sounded better than dubstep. I took a video of the bats darting around using the last glow from the sun (click here). Give yourself ten minutes to watch, listen, imagine sitting by a lake and enjoying a Texas summer evening while bats dart above the dark reflections of mountains in the lake. I wish this video could capture the fireflies blinking in the deep shade below the pecans and oaks. The bats darted incredibly close in front of us before veering to fly just over our heads. We realized as we sat on the boardwalk that perhaps the bats incredible appetites for insects were the reason we weren’t getting eaten alive by the mosquitoes, who were drawn to the water to lay their many eggs. I felt incredibly at peace with no bugs biting me and bats flying above as the light faded and the frogs continued singing to each other.