More Onion Creek floods likely, hydrology expert concludes


A study of the Onion Creek Halloween flood performed by a University of Texas expert showed the flood was not a unique event for the area and that the city should be ready for similar events.

David R. Maidment, a UT professor of hydrology, gave a presentation that showed while the flood was severe — with storm surges equivalent to a Category 3 hurricane — flooding that damaged hundreds of homes fell within normal statistical predictions.

“This was not something that was an act of God,” Maidment said.

Maidment also said there may have been some misplaced blame on faulty flood gauges that malfunctioned as the creek crested. Greater use of other measurement tools outside of the city of Austin could have shown a flood was coming, he said.

His analysis pegged the flood as one so severe it should happen about every 50 years. But Maidment and officials at Monday’s Public Safety Commission noted that his estimation was only based on averages and showed it should not be a shock to see similar flooding once every 15 years.

Maidment examined the uniqueness of the flood, whether development exacerbated the situation and future risk to the area as well as characteristics of the Onion Creek Watershed.

The watershed is larger than the entire city of Austin, stretching from Dripping Springs to Buda to Austin-Bergstrom International Airport. Within that area rainwater flows from small tributaries to the meandering portion of Onion Creek where the flooding occurred and eventually to the Colorado River east of Del Valle.

Maidment concluded that development did not increase to the severity of the flood. The heaviest rains fell far upstream from the Onion Creek neighborhood. But he did not rule out it having an affect in any future event where the worst rain might be falling in the area of the flood.

Commissioners unanimously voted in support of Maidment’s suggestion that the city participate in a larger national conversation about water issues and that the Halloween flood be submitted as a case study to federal agencies.

“I don’t think this is Austin’s problem to solve alone,” he said.


Reader Comments ...


Next Up in Local

Downtown’s Waller Creek oasis begins with Waterloo Park improvements
Downtown’s Waller Creek oasis begins with Waterloo Park improvements

A chain of parks and trails more than five years in the making will break ground Wednesday on its first phase, with an ultimate goal of restoring Waller Creek, connecting Central and South Austin trail systems and lining downtown with green space. The Waller Creek project will run from Waterloo Park, near Trinity and 12th streets down to where the...
With no Democratic governor candidate, questions trail Joaquín Castro
With no Democratic governor candidate, questions trail Joaquín Castro

Exiting a summit on citizen diplomacy Tuesday at the Texas Capitol, U.S. Rep. Joaquín Castro, D-San Antonio, was trailed by a handful of reporters. “Something tells me you didn’t come to hear a speech about international affairs,” Castro said. He was right. The reporters were there to once again ask whether he would consider...
Ken Paxton prosecutors appeal payment-blocking ruling
Ken Paxton prosecutors appeal payment-blocking ruling

Three lawyers appointed to prosecute Texas Attorney General Ken Paxton on Tuesday asked the state’s highest criminal court to overturn a lower-court ruling that blocked them from getting paid for more than a year of work on the case. Unless overturned, the ruling “will have a chilling effect on the ability of trial judges to appoint qualified...
Police: Suspect in hike and bike trail sexual assault arrested

CENTRAL AUSTIN Police: Suspect in trail sex assault arrested A suspect was arrested Tuesday morning after a woman reported being attacked while she was running around Lady Bird Lake last week. The suspect, 22-year-old Richard Jordan McEachern, was charged with sexual assault and booked into the Travis County Jail on Tuesday morning, records show. His...
House official blamed for crimping felony charges against Rep. Dukes
House official blamed for crimping felony charges against Rep. Dukes

After announcing last week that they are holding off on the most serious charges in the corruption case against state Rep. Dawnna Dukes, Travis County prosecutors revealed the reason in a court filing Tuesday: A House official has given conflicting statements about rules on state travel reimbursements that are at the heart of the 13-count felony indictment...
More Stories