AUSTIN, Texas -- A new study of our region's floods the past 25 years has local leaders redesigning major infrastructure projects. Additionally, many homeowners are learning they're about to be in a floodplain for the first time.
• Flood risk is rated on a three-tier scale
• 100-year floodplain may require homeowners to purchase flood insurance
• In November 2017 voters approved $93.4 million for road projects
Brenda Winn has lived in Northeast Austin's Las Cimas neighborhood for almost 40 years. Last month, she received a letter from the City of Austin informing her that her property would soon be within a 100-year floodplain.
That means her property could experience a flood once every 100 years.
"I thought, 'Well, they're crazy,'" she said of the letter. "I am trying to figure out what is going to change that would make us really going to flood."
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Flood risk is rated on a three-tier scale, where 25-year is the most prone to flooding and 500-year floodplain is least likely to flood. However, a 100-year floodplain may require homeowners to purchase flood insurance.
"Flood insurance is so high, so you have to think about: if it is going to flood, how far is it going go, what is this going to do," Winn said.
Winn said her neighborhood experienced minor flooding in the 1980s, but the floodwaters never reached her property.
"After the flood, they did build a wall," Winn said. "We thought we were safe."
A neighbor who lives right next to the creek said the Memorial Day Weekend 2015 flood brought Walnut Creek within six inches of the top of the wall.
Travis County Commissioner Brigid Shea said the new maps, crafted using rainfall data from 1994 to 2017, puts thousands of Travis County properties like Winn's in a floodplain.
"With this new data, it shows that we have to elevate even higher," Shea said. "I realized about seven or eight years ago we are not doing enough to help people get out of harm's way."
In November 2017, Travis County voters approved $93.4 million for road projects. However, Travis County Commissioners had to shell out an additional $31 million Tuesday to revise engineering designs for those projects. The modeling data showed ditches often needed to be dug deeper, culverts widened and bridges and roadways built higher than designed under the existing 100-year floodplain maps.
Several roads built within the past decade will also need to be replaced with higher ones, including one near the Circuit of The Americas and SH-130 where two people were washed away by floodwaters in May 2016. Shea said businesses--including the racetrack--should be cover part of the costs of the necessary road improvements.