The city’s recent acquisition of the Anthem Tract in Hays County, which includes the Mustang branch of Onion Creek, was funded by a $72-million-dollar bond passed by Austin voters in 2018. Like water on other city-managed land surrounding Onion and Barton creeks, the Anthem Tract’s groundwater feeds into Barton Springs.
Guides for the June 14 tour said the newly purchased tract was not available for touring due to heavy mud, but were able to explain the city’s water research and conservation procedures at the Onion Creek Management Unit, also in Hays County.
The tour included a demonstration of the use of filters to increase water quality entering caves in Onion Creek that feed Edwards Aquifer. According to Kevin Thuesen, environmental conservation program Manager for Austin’s Water Quality Protection Lands, water from the Onion Creek watershed contributes 33% of the water in Barton Springs, and water from the Onion Creek Management Unit takes just three days to feed into the springs, making impurities important to manage.
“Instead of just buying the land and sitting on it and saying that’s good enough, what the city has done is we’ve created a land management plan that’s renewed every 10 years and says, ‘Here’s how we’re going to manage this land to protect water quality,’” Thuesen said.
Management include ecological restoration processes to convert lands back to their natural states as savannas and prairies with techniques including prescribed fire and brush cutting, Thuesen said. He said that city and volunteer efforts have also succeeded in protecting and increasing biodiversity on the land.
After 20 years of effort to preserve land in the Edwards Aquifer recharge zone, the city has protection rights of close to 29,000 acres, according the David Johns, a geologist with the city’s Watershed Protection Department. Those acres include conservation easements, agreements with private property owners to preserve and protect their land.
“The focus back in 1998 when we started this program was protecting the Edwards Aquifer and Barton Springs,” Johns said.
Present day, he said the program has expanded their goal to protecting the water quantity and quality of other bodies of water upstream, from Barton Springs Pool to Lady Bird Lake.
“We’re doing things out here that will be here forever, and forever is a really great time frame to work with,” Johns said.