Did you know that the Pedernales River, along with the San Saba, the Llano and the Concho Rivers, flows into the mighty Colorado River. This Colorado River flows only in Texas; it is definitely not the same one that runs through Utah and Arizona. Still, it is the longest river in Texas and the livelihood of many depend upon it.
Here is a map of the Colorado River watershed:
It is easy to see that the Colorado River watershed includes the Edwards Plateau. What you may not be able to discern is just how important this watershed is. There are over 7,500 miles of creeks, streams, and rivers in the Colorado River watershed, and well over 2 million people live and work here. The Colorado’s watershed includes several major metropolitan areas, including Midland-Odessa, San Angelo, and Austin, and there are hundreds of smaller towns and communities as well. Many communities, like Austin, rely on the Colorado River for 100% of their municipal water.
With karst geology throughout the Hill Country, all water is considered connected. Karst is a type of landscape where the dissolving of the bedrock has created sinkholes, sinking streams, caves, springs, and other characteristic features. Karst is associated with soluble rock types such as limestone, marble, and gypsum. Karst geology means that throughout the Hill Country, water flows in channels beneath the surface, through geologic features cut by the flow of water over a millenia. So even if one town has wells and another gets their water from the river, because of the way the aquifers flow through the limestone beneath us, we must consider all of this water as connected. Excessive water use, impacts adjacent areas. Rain that falls on Midland, will be flow through the river and through the underground channels to locations further south. Pollution up stream, flows downstream.
Did you know that the most common pollutant in American waterways is dirt? Water quality can be impacted negatively by a number of things, almost all of which are connected to human activity. When you see a plastic bag or wrapper blowing along the street, rain will likely carry it into a storm drain and from there into a local creek, and it will eventually end up in the Pedernales River and on to the Colorado River. This visible pollution is unsightly and damaging to aquatic ecosystems.
Fertilizers, weed killers, and pesticides all wash off yards and fields and into our waterways as well. This invisible pollution is harder to spot, and over time it can build up in our waterways with devastating results. (For instance, click here for a current list of golden algae blooms in the Colorado River being investigated by Texas Parks & Wildlife.)
Chemicals dumped from an industrial site is an example of “point source” pollution, because it comes from a specific source. Fertilizer run-off is an example of “non-point source” pollution because it can come from many places at once — making it harder to prevent. For more information on what Texas is doing about non-point source pollution in our waterways, click here.
With our current drought, many people ask, “Will we run out of water?” That is hard to predict but it is not possible to answer, “No” to this question. Our current rate of water usage, especially in the Hill Country and the communities outside of Austin, is very high. Development is not slowing so demand will only increase. In order to ensure we have water for the future, one of our most important steps will be to reduce the amount of water used per capita per day. Conservation of our rivers and water sources are imperative.
This recent report outlines all of the threats to our water, night skies and more. If you find this report alarming, and hopefully you will, know that it is a wake up call for all of us.
STATE OF THE HILL COUNTRY
8 Key Conservation and Growth Metrics for a Region at a Crossroads
February 2022