Tue November 27, 2012
Video: Inside Downtown Austin’s Waller Creek Tunnel
In May, the City of Austin invited members of the news media into the Waller Creek tunnel.
Meeting at the construction site at Fourth Street and I-35, reporters traveled down a 26-foot wide shaft, in a metal box lowered by a construction crane. At the time, some 1,300 feet had been excavated. When we checked back in in September, over 3,200 square feet had been excavated.
Above ground, the tunnel is designed to keep flood-prone Waller Creek in its banks. And just what to do with the acres of land pulled out of the flood plain is a hot topic: in October, a design team was named to plot the transformation of the Waller Creek area.
But back underground, some wonder if the relative ease of tunnel construction means Austin should dig another tunnel: one for a subway.
KUT News reporting project StateImpact Texas tackles that question today. Gary Jackson, the city’s public works project manager, tells StateImpact Texas that the tunnel is nearly identical to what would be built for a subway tunnel.
Credit lies with Austin’s geology. Joe Pantalion, Deputy Director of the Watershed Protection Department, told KUT News in September that “the Austin chalk limestone that’s 60 to 70 feet below Austin …. is some of the best material to tunnel through. … It has enough hardness to tunnel through without requiring a significant stabilization system. But at the same time, the excavation is not like cutting through butter, but pretty close.”
But Pantalion added that “subway systems are very different than a flood control tunnel. Flood control tunnel is simply just putting the concrete in. A subway, you have to have fire safety egress, ingress, ventilation – there’s a lot more to building a subway in Austin than just digging a tunnel.”
Austin Transportation Director Robert Spillar pointed out another issue to StateImpact Texas: cost. “It used that areas could count on the federal government for paying 80 percent of the cost. Now you have to pay most of it locally. The best you can do is 50 percent.” And the added cost of tunneling is something Spillar says Austin couldn’t afford.
Videographer Jeff Heimsath shot these scenes inside the Waller Creek tunnel back in May. Take a look, and let us know: Would this be the perfect spot for a subway?