In the wake of Hurricane Harvey and with the knowledge that parts of the city have badly flooded twice during the month of October in the past four years, Austin’s Public Safety Commission on Monday invited former and current city officials to speak at its monthly meeting about the ways the city is — and isn’t — prepared for flooding disasters.
Some upgrades to Austin’s early warning system have been implemented since major floods in 2013 and 2015, and some upgrades are still in the works, officials told commissioners.
Most notably, Austin covered some of the costs to replace the U.S. Geological Survey gauge along Onion Creek that washed out during the Halloween floods of 2013, said Kevin Shunk, engineering division manager of the Austin Watershed Protection Department. Crews placed the gauge “higher this time, with additional equipment inside so it could withstand more force from the floodwaters,” Shunk said.
Crews installed similar equipment at a gauge along U.S. 183 that, during that same flooding event, temporarily stopped functioning.
The Austin Watershed Protection Department is working to install cameras to monitor low water crossings in real time, he said. The feed of at least one — near River Plantation Boulevard along Onion Creek — is available to view on atxfloods.com, and the department is testing more internally.
The city’s staff says about 4,000 houses in Austin would flood in a 100-year storm and about 10,000 would have water around them.
“If you’re in a 100-year flood plain, your house has a 26 percent chance of flooding over a 30-year mortgage,” Shunk told the commission.
The city has purchased 801 properties in Onion Creek to prevent people from living in that flood plain. Whenever flood plain maps are updated, Shunk’s department notifies people living in the affected properties via postcard, and his department has begun to notify those living near the flood plain as well, he said.
Shunk said prospective homebuyers often end up making decisions about a house without being provided any flood plain information. Only homebuyers using a federally backed mortgage — which will require them to purchase flood insurance — are notified when the house they’re looking to buy is in a flood plain, he said.
“Otherwise, no one’s going to tell you,” he said.
Shunk said he is also concerned for renters, who are likely to be unaware if they live in a flood plain.
Elsewhere, the city has bought out homes near Walnut Creek, Johnny Morris Road, Shoal Creek, Jefferson Street, Carson Creek and February Drive and in the Bull Creek Watershed.
The commission asked Shunk questions about the city’s urban development code and any proposed changes to it related to flood mitigation.
Shunk told the commission he does not believe CodeNext — the master plan being developed to outline recommendations to modify Austin’s city code — would create any adverse flooding effects. That’s because the plan does not change the city’s current ordinance, which says new development cannot cause flooding on other properties, Shunk added.