Ascension Seton Construction Plans Threaten Water Flow

Shoal Creek Conservancy volunteers in Seiders Springs plant live oak, rough-leaved dogwood, and Mexican buckeye to reintroduce native species and improve the habitat for wildlife (Photo by Leila Saidane)

Seiders Springs, a centuries-old peaceful green patch squeezed into the center of Austin, retains only a trickle of the gushing flows it was once known for. That may slow to a drip, the Shoal Creek Conservancy worries, if Ascension Seton Medical Center doesn't revise their current development proposal to build an underground parking garage right where the springs water source flows.

The hospital is proposing a new women's and children's tower and cardiovascular wing at its main campus on 38th and Lamar, with accompanying above- and below-ground parking garages. City code prevents development within 150 feet of a critical environmental feature like Seiders Springs. Although Ascen­sion's new wing complies, "That … does not necessarily protect the groundwater threat that we're facing [from] the underground garages of this site," says Ivey Kaiser, Shoal Creek Conservancy director.

The excavation the construction requires has the potential to intercept the ground­water flow to the springs, Austin hydrogeologist Sylvia Pope says. These paths can't be mapped from the surface. "Once the groundwater flow is intercepted, then that has the potential to cut off flow to Seiders Springs," Pope says. "The most … simple solution would be to avoid any excavation and to build the parking structures entirely aboveground."

The Shoal Creek Conservancy already works to protect the creek from the effects of natural disasters and non-native vegetation, but steel-reinforced concrete is a bigger interloper than the invasive species the conservancy regularly uproots. Interfering with the spring flow at this key natural and historical site has additional implications. The wetland zone the conservancy is working to restore, with healthy native grasses, may dry up. That in turn may impact Shoal Creek's base water flow, expanding the threat beyond the environs of Seiders Springs to the entire ­creekway.

The hospital intends no harm in construction, Ascension Chief Strategy Officer Raymond Anderson said in a letter of commitment to the conservancy, and will further study the impacts of the garages before moving forward with design. "While the Medical Park Tower site is not the subject of the pending Planned Unit Development Amend­ment before City Council, nevertheless, we understand the Shoal Creek Conservancy is focused on protecting Shoal Creek and in this specific area, Seiders Springs from any harm including obstruction of groundwater flows," the letter stated.

Kaiser says SCC's only ask is for Ascen­sion to not construct any underground parking facilities, and they'll stay in contact to ensure designs will protect the creek. "We are very encouraged by [Ascension's] sentiment and hope to continue to work with them [so that] whatever does come of the new parking garage … does not have a negative impact on the Springs or Shoal Creek," Kaiser says. "We're hoping to find a way to … protect these springs for future generations and [do the same] for all of the habitat and natural environment" of the creek.