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Energy and Environment Reporting for Texas

Near-Catastrophe During Flooding Highlights Issues at Dam in Austin

Crews work to dislodge a barge from Longhorn Dam. The dam that creates Lady Bird Lake in downtown Austin.

Austin Energy

Crews work to dislodge a barge from Longhorn Dam, the dam that creates Lady Bird Lake in downtown Austin.

A lot of people who walk or drive past Lady Bird Lake in downtown Austin probably assume it’s a natural feature. They appreciate the trails and parks that line the lake’s 416 acres, unaware of the series of floodgates on the Longhorn Dam that hold its waters in. But recent flooding along the waterway has called attention to longstanding mechanical problems at the dam, problems that the City of Austin is aware of, but hasn’t found the money to address.

While its been called the “jewel in the crown” of Austin, Lady Bird Lake was created to serve a utilitarian purpose: to provide water for a now-decommissioned gas power plant in the Holly neighborhood of East Austin. Because of its connection to the power plant, the dam is operated under the supervision of Austin Energy, the city’s publicly-owned electric utility. Built in 1960, the floodgates on Longhorn Dam have stored and released water from the lake for over 50 years. Now that age is showing.

“There’s been a lack of maintenance on the dam for the last 15 years,” Dennis Hipp, a recently-retired Austin Energy employee tells StateImpact Texas. “It’s steadily gotten worse and it’s to the point now where it’s going to start doing some damage. [Both] upstream and down.”



Hipp spent some of his 24 years at the Holly Power Plant operating the dam’s floodgates. He wanted to share his concerns in the hope that it would encourage the city of Austin to invest in repairs.

Now that the power plant is gone, there’s nobody close at hand to control the floodgates. Hipp says that’s a serious problem, because the gates need to be manually opened and closed in response to quickly changing water levels.  Adding to the challenge is the fact that dam’s seven floodgates suffer from mechanical problems.

One of the gates is completely broken.  It’s been sealed with a huge steel block called a “stop log,” a tool usually used for dam repairs. That reduces the amount of water than can be discharged from the Lake in times of flooding.

One floodgate is completely broken and has been blocked with a "stop log."

Mose Buchele

One floodgate is completely broken and has been blocked with a "stop log." This gate will not release water when it floods.

“That [stop log] is really just for maintenance,” Hipp says. “That’s not a permanent solution. And it’s been in there for probably six, seven years now.”

Other gates still open but are difficult to close, forcing work crews to improvise.

“Sometimes, they can take a stop log and they can bump, you know, one end of the gate or the other,” Hipp says. “They use it for weight.”

Much of what he describes is corroborated in two engineering reports Austin Energy commissioned. One was intended to provide a conceptual design and cost estimate for repairs to the dam (embedded below) the second report (provided by Austin Energy in “draft form,” and incomplete) was on the possibility of building a whole new dam.

Those reports say problems with the floodgates create a dual risk. They have contributed to flooding upstream, and created the possibility of the lake draining out if the floodgates don’t close.

Adding to all those challenges? The crews that control the gates during a flood are working in some of the worst possible conditions: amid heavy rain, winds and lightning.

“Most people in Austin just assume that [the gates] are automatic,” Hipp says. “Because it’s all done at night or in terrible weather where nobody’s out.”

That’s how it was the night of the Halloween floods.

Avoiding a ‘Catastrophe’

Crews work to dislodge a barge from Longhorn Dam in Lady Bird Lake on Halloween 2013.

Photo Courtesy of Austin Energy.

Crews work to dislodge a barge from Longhorn Dam in Lady Bird Lake on Halloween 2013.

The problems that night aren’t connected to the flooding that took lives and destroyed homes elsewhere in Austin at Onion Creek, but they do show how difficult the situation has become at the Longhorn dam and can cause flooding downtown.

Communications obtained through an open records request from Austin Energy show that a work crew arrived at the dam to start opening gates around 11:10 p.m., right as the Lower Colorado River Authority (LCRA) began discharging water from Lake Austin upstream.

As heavy rains persisted, the LCRA released more and more water in Lady Bird Lake, reaching peak discharge at 1:25 a.m. About 20 minutes after that, work crews faced a challenge that, in the words of one Austin Energy Employee, brought them to the brink of “catastrophe.”  Construction barges from the Lady Bird Lake Boardwalk project washed down the flood waters and into the dam. They jammed into two of the operable floodgates.

“It certainly complicated our operations that night,” Cheryl Mele, Chief Operating Officer at Austin Energy, tells StateImpact Texas. “At some points that night when we should have still had gates open, we did have to reduce the flows through the dam to make sure that we could secure and get those barges removed from the dam. So certainly that might have contributed a little bit [to the flooding].”

Outside of Austin Energy employees and emergency responders, there are few witnesses to the flooding on the lake. One of them was photographer Reagan Hackleman, who walked to Auditorium Shores when he heard the LCRA was releasing water downstream. He took the now-iconic photo of the flooded Statue of Stevie Ray Vaughn.

Hackleman says he watched the lake rise four or five feet in around 20 minutes, flooding César Chavez street and the lakeside park. That was around 2:30 a.m., approximately 40 minutes after the barges lodged in the dam.

A statue of Stevie Ray Vaughn wait-deep in water, taken the night of the flood.

Photo by Reagan Hackleman.

A statue of Stevie Ray Vaughn waist-deep in water, taken the night of the flood.

“When I took the picture, the water was up to my chest. And I’m a tall guy, I’m like 6-3,” he says.

Austin Energy COO Cheryl Mele agrees that the problem of the unmoored barges, coupled with the fact that one flood gate is sealed shut, did contribute to the buildup of water. Though she says that flooding would have happened even if everything had run smoothly.

“What we saw along Lady Bird Lake was the contributions of the LCRA needing to release water from Lake Austin, as well as the inflows coming in from Shoal Creek, and Waller Creek and Barton Creek,” Mele says. “Remember we were talking about unprecedented flooding levels.”

Data does show how more water was entering the Lake than was exiting. According to information obtained from an LCRA open records requests, the peak discharge of water from the Tom Miller Dam, upstream of Lady Bird Lake, was over 43,000 cubic feet per second around 1:25 a.m. The peak discharge of water downstream of the Longhorn Dam was around 34,000 cubic feet per second. Regardless of whatever other water was flowing into Lady Bird Lake, this suggests that Longhorn Dam was unable to handle the amount of water sent to it when the Tom Miller is discharging at peak capacity.

The fact that more water was entering the Lake than could exit, causes Dennis Hipp to conclude that much of the downtown flooding could have been avoided with better planning and a properly functioning dam.

Reagan Hackleman revisits the statue in better weather.

Mose Buchele

Reagan Hackleman revisits the statue in better weather.

“None of that downtown flooding had to happen,” he says. “Everything has to do with the dam, because if the water’s not going out, there’s no place for the creeks and ditches to drain to.”

Communications records show the sense of urgency late that night and into the morning. According to a log kept by the LCRA, Austin Energy crew called them to ask them what to do about the barges, saying they weren’t sure if they would be able to close the floodgates when they needed to. The LCRA advised they call the city’s emergency management department.

Eventually, around 9:25 in the morning, the team did free the obstructions with the help of contractors. But the troubles at the dam were not over.

Water Levels ‘Plummeting’

At 7:30 pm on Halloween evening, after the rains had ceased, the LCRA noticed that Lady Bird Lake, which earlier had flooded, was now draining – quickly.

According to the LCRA’s communications log, the agency contacted Austin Energy to say lake levels were – in their words – “plummeting.” Austin Energy replied that the flood gates had been closed and everything was under control. Seeing water levels continue to drop, LCRA called again, urging Austin Energy to make sure the gates were closed.

Cheryle Mele is the COO of Austin Energy.

Mose Buchele

Cheryl Mele is the COO of Austin Energy.

At 8:30 pm, Austin Energy called back to confirm that one floodgate on Longhorn dam had not closed properly. Austin Energy COO Cheryl Mele says that communications “weren’t as tight as perhaps they could have been.”

“[The gate] probably had debris under it, preventing it from going down and so we lifted it, let things flush and re-seated that gate,” she tells StateImpact Texas.

The problems with closing the gate echo challenges outlined in the engineering studies commissioned by Austin Energy, which say that equipment “frequently malfunctions” and that in the past the lift gates “have failed to open or close properly.”

An Acceptable Level of Flooding

The flooding that took place along Lady Bird Lake had a minimal impact compared to flooding elsewhere in Austin that night.  Parts of Cesar Chavez street downtown were submerged – something that would not happen if the dam operated properly, according to one study. But in most places, the waters only flowed over parkland. Along the hike and bike trail, the worst damage discovered by StateImpact Texas was debris and dead fish left by the retreating flood waters.

Flooding has happened along the lake since before the dam was constructed, and Austin Energy’s Cheryl Mele says some flooding will always be a possibility in severe weather events.

“That’s one reason we do not have things along Lady Bird Lake, because there’s a flood plain,” she points out. As far as the dam is concerned, she says the maintenance problems do not threaten anyone’s safety.

According to one of the engineering studies, repairing Longhorn Dam would cost around $16 million. That’s money Austin Energy says it doesn’t have. And if the city did have that money, one could argue that it would be better spent on other flood remediation projects, like buying out houses in the floodplains of Onion Creek, where waters caused massive property damage and loss of life unrelated to the the operations of the Longhorn Dam.

“Would it be nice to have everything modernized? Sure,” Mele tells StateImpact Texas. “But it will take some planning to make sure that will be considered in future budgets. But there’s no urgent safety issues.”

In the absence of repairs, Austin Energy has been trying, unsuccessfully, to give control of the dam over to another group. The LCRA was approached about taking over operations, but the deal never went through.

For critics of the dam, like Dennis Hipp, each day that repairs aren’t funded is a day that brings the city closer to major flooding on the lake, or the surreal possibility of Lady Bird Lake draining out completely.

“Ever since I’ve started my career with Austin Energy, there’s always been issues with the dam. We’ve constantly sent emails, work orders, and nothing…” he says. “Just band aids have been put on it.”

Comments

  • MJ
  • PPIH SINNED

    There are SO MANY inaccuracies in this article it should not have been printed.

    1) First the amount of water discharging from Tom Miller Dam combined with the flow of Barton Creek caused the flooding of the area near the Stevie Ray Vaughn Statue, NOT THE CONTROL OF LONGHORN DAM. Lady Bird Lake is not a bathtub. Simply opening the drain (Longhorn Dam) doesn’t impact the water level in that area near the statue for hours. Lady Bird Lake would have had to been drained to prevent that flooding. Look at a map, that area of the lake is shallow and narrow. It does not take a rocket scientist to realize adding a significant volume of water in an area like that and you will get flooding, period.

    2)The timeline of the barges hitting the dam and the time of the photo will show the barges didn’t cause the flooding in the top of the lake, Barton Creek did.

    There were a LOT of hard working people who were risking their lives manning that dam in the pouring rain and lightning. Quoting ex-employees of an organization with their speculation on what happened that night is poor inaccurate reporting. There will always be flash floods in Central Texas and as much as no-it-all’s think we can control Mother Nature, we cant, we can just do our best to prevent as much damage as possible and keep everyone safe.

    • Mose Buchele

      Thanks for reading SINNED,
      The perspective you’ve shared is
      presented in this story, so I’m somewhat baffled by your tone. However,
      a draft study about the dam commissioned by AE does find that “Cesar
      Chavez would not flood with the existing structure as long as the gates
      are operated correctly,” indicating that -at least in some rain events- the dam does impact upstream conditions. I’ve spoken
      with others beside Hipp who also see a connection there so I included
      that perspective as well. While Lady Bird is not a bathtub, it is a
      river. The water upstream needs to flow down the river eventually, and
      when it encounters an obstruction that changes the nature of the flow. Thanks again!

      • PPIH SINNED

        2010 – Lady Bird Lake flooded OVER PLEASANT VALLEY ROAD yet Stevie’s feet stayed dry.

    • stagr.lee

      The article has good info. It sounds like it takes hours to get a dam
      operator over to Longhorn so the delay becomes an issue for downtown
      property. The delay coupled with a mechanical failure could have been
      really bad. The photographer pointed out the levels came up in 20
      minutes at 2:30AM, so your point about initial flooding seems valid to
      me. But the author’s point was Longhorn peaked at 34K cfs which means if
      the rain kept going we would have had the dam spill and likely wash
      away down to Bastrop potentially causing loss of life down stream.

      I’m only seeing Barton Creek flowing at 8K cfs so the 43K coming out of Miller is more likely the cause.
      http://waterdata.usgs.gov/nwis/uv?cb_00060=on&cb_00065=on&format=gif_default&period=&begin_date=2013-10-30&end_date=2013-10-31&site_no=08155300

      I
      agree with your point about worker safety, I object to Cheryl Mele’s
      statement, “But there’s no urgent safety issues.” Her employees and
      contractors were working in a river system flowing 43K cfs plus whatever
      Barton, Shoal, and Waller creeks were flowing (>60K cfs?). I’m
      thankful no one got hurt. But, I give credit to Mr Hipp for pointing out
      the job risks confronted by his former co-workers and management who
      discounts that risk. I’m glad an ex-employee explained this to the
      public.

      Also, as Mose Buchele points out, we need way more than 34K cfs worth of flow out of Longhorn.

  • pipercub

    not sure i understand your comment sinned. making room for water near the longhorn dam (opening floodgates), would that not help?

    • Thinking.

      I think what he is referring to is the time delay with the moving water. It takes time for the water to travel from Tom Miller Dam through Lady Bird Lake to the Longhorn Dam. That increase in water along with the addition of Barton Creek will hit the shallow area above the S. 1st St. bridge and rise up above the banks. It is possible that the barges affected how long it took to lower the lake though. I am not sure because I didn’t pay much attention to the timeline of things. To me it appears that people responded fairly well given the extenuating circumstances during an infrequent yet extreme event. How do you plan for a flood? Don’t build in the floodplain.

      • stagr.lee

        The wave propagation of a surge of water released from a dam is well documented by river boaters in the Grand Canyon. In that river, the wave runs about 4 MPH down stream with the peaks and valleys getting less pronounced as you get further from the dam. The boaters use this to calculate what time to run the rapids.

  • adbirds

    Perhaps LCRA could or should fund the dam repairs from here on. What do you think?

    • Thinking.

      I do not think LCRA has any interest in helping to maintain the dam. It does not provide them with any services so it would not make economic sense for them to become involved in it’s maintenance. The only purpose for the Longhorn Dam is to provide the citizens and visitors of Austin with a local waterbody on which to recreate or view. It does seem to me that Austin, the government and citizens, will have to decide if they want to pay the money to continue having a reservoir in the downtown area because that and all dams require maintenance.

      • adbirds

        Perhaps the city could come up with funds to create a concrete spillway and be done with dam maintenance for good.

  • jhvtex

    Since the Holly Street generating station no longer operates or requires
    water impounded behind this dam for cooling or steam production,
    perhaps it would be best for Austin Energy to either spend the money
    required for the dam to operate properly in conjunction with upstream
    LCRA dams or simply sell the dam to LCRA for $1 and allow that latter
    special-purpose institution to perform the necessary repairs and
    mechanical upgrades so it can be operated responsibly when flood events
    occur along the broader Colorado River watershed. If LCRA and AE were
    to undertake the required (but long-deferred) maintenance action on a
    joint-venture basis, it would be highly desirable to install
    run-of-river hydropower generation capability for the low-head structure
    and enhance electrical production for both Austin Energy and LCRA from
    the predominant renewable resource available in this region.

  • SD2AUS

    Really? Austin Energy is in charge of a dam that control water flow down stream? I would have thought it would be the Lower Colorado River Authority’s (LCRA) job. No wonder Lake Austin and Ladybird Lakes are at constant levels while Lake Travis and South of Ladybird are in trouble (follow the money; it’s pretty for the tourists). What are we waiting for—this sounds like New Orleans, La., we as Federal Tax payer have bailed out several times in my life time. Gotta love a City that is built at/on Sea Level. STOP kicking the can. I was aghast that the City of Austin is buying flooded homes in Onion Creek (clearly noted to be in a flood plan). Perhaps this is the City of Austin’s way of saying whoopsy. Clearly this is not something we as Austin residents can ignore. I happen to think that the only reason there were not numerous injuries and deaths is that it happened early in the morning, on a rainy, cold night where people had the good sense to be inside/at home. It DID create property damage, and once again, we are PAYING FOR IT!

  • jess

    Maybe they should have used the $20M to build an elevated walkway to fix the dam.

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