By Taylor Turner, Garrett Callahan, Jacob Kerr and Kylie Fitzpatrick
As Austin’s population continues to rise, so do the construction zones on the city’s roadways.
Between 2011 and 2016 Austin is expected to have a growth percentage of 6.1 percent, according to Forbes, making Austin one of the fastest growing cities in the country. And to combat the extra population, the Texas Department of Transportation and the Central Texas Regional Mobility Authority have already begun several construction projects they believe will increase mobility and traffic in the Austin area.
But many local environmental groups believe there is a significant threat to the local ecology as construction projects develop.
One of the projects is the Mopac South expansion project, which would build two toll lanes in each direction from Cesar Chavez to Slaughter Lane in addition to a double-decker bridge crossing Lady Bird Lake. The plans also pass over a segment of the Edward’s Aquifer, which runs into Barton Springs.
Activists against the construction said the project would increase pollution in the spring’s waters with the rise in traffic. According to Keep Mopac Local, an initiative against Mopac’s construction plans, the project would add up to 60,000 travelers per day in addition to the 130,000 cars that already use the highway. The organization said the additional travel would increase urban runoff and pollution in the Barton Springs waters.
“The water that goes into this aquifer doesn’t have any sort of filtration so pollution that goes into this aquifer goes into Barton Springs,” said Aubrey Cravotta, an outreach coordinator with Save Our Springs Alliance, which is part of Keep Mopac Local.
Cravotta said one of the consequences of any increased pollution is the further endangerment of species living in Barton Springs, including the Barton Springs Salamander.
The Barton Springs Salamander, a small, completely aquatic salamander, became formally recognized in 1993. The salamander only lives in Barton Springs in Austin, but has become increasing less visible in the Zilker Park waters.
In late April 1997, the Barton Springs Salamander was listed among the U.S. Endangered Species after its population sharply declined entering the 1990s. According to the Texas Parks and Wildlife Department, the salamander had a large population in the early 1970s, but has since fallen due to pollution in the waters.
The waters the salamanders are found in are feed by a small segment of the Edwards Aquifer, which is influenced by rainwater and water flow. However, this also presents an opportunity for contaminates to run into the water that can endanger the species living there.
Most species of salamanders, once they reach adulthood become terrestrial, no longer keeping their external gills. However, the Barton Springs Salamander stays aquatic for its entire life, retaining its juvenile characteristics and external gills to breathe.
If pollution and other contaminates, which Cravotta said has the ability to increase with the construction project, inhibit the waters, the salamander’s ability to breathe will be prohibited, which has resulted in its population decline in past decades.
“That’s why the species was put on the endangered species list because of these true threats of and possibility of contaminants affecting the entire species at once,” said Dee Ann Chamberlain, an environmental scientist with the Austin Watershed Protection Department.
To help combat the declining population, the City of Austin has set up a Captive Breeding program within the Austin Watershed Protection Department, which helps maintain the Barton Springs Salamander’s population.
“The idea is to have a population of the species in captivity that you could introduce into the wild if something happened to the species,” Chamberlain said.
Chamberlain also said the Captive Breeding program helps the city better understand how the species lives. Since the Barton Springs Salamander lives mostly underground, the program allows for the species habitation to be seen first hand.
“Parts of their life history is difficult to understand looking at them in the wild so we’ve had to study their life history working with them in captivity,” Chamberlain said. “It’s like thinking of it as putting together different pieces of a puzzle to put together all the different parts.”
Currently, the Central Texas Regional Mobility Authority and the Texas Department of Transportation are in the last year of an environmental study that looks at the environment impacts that the expansion project could cause. At the end of the year, if the study finds to have any impact on the Barton Springs Salamander or any other endangered species, the Central Texas Regional Mobility Authority said it would take steps to fix them.
“At the end of the year, there is going to be a final report were all those issues will be identified,” said Rick L’Amie, the communications director with the Central Texas Regional Mobility Authority. “It’s too early to say what [the issues] are right now because we are still studying it.”