With flooding becoming a frequent worry in Houston, local officials are eyeing other Texas cities' attempts at building so-called flood tunnels to divert storm water.
San Antonio has had flood tunnels for over two decades. Austin is just finishing a tunnel while east Dallas is now forward on one.
Houston officials say it's something worth considering for the Bayou City.
“In lieu of acquiring a significant amount of right-of-way and taking a significant amount of properties off the tax rolls and actually building a tunnel system that will handle extreme events, that might be a cost-effective approach,” says Steve Costello, the city of Houston's chief resilience officer.
The tunnels would take water from current bayous underground and into the Ship Channel.
“We're talking very large tunnels, 40-foot diameter tunnels 100 to 150 feet under ground,” he says. “It could follow major transportation corridors like a major thoroughfare or even a highway and be deep enough where it's not impacting foundations and will have minimal impact on the environment.”
However, the tunnels could cost up to $100 million per mile.
“There's quite a bit you could build with several billions of dollars and have the protection you're really wanting to accomplish,” says Costello.