If the Addicks and Barker Dams Fail

They've already been labeled "high risk." Experts say the resulting damage could be bigger than Katrina in New Orleans.

Before June 2001's Tropical Storm Allison, which destroyed 90 of 105 buildings on the University of Houston campus, and Hurricane Ike in 2008, dam-less Houston had to swim its way out of the devastating Memorial Day flood of 1929, which caused Buffalo Bayou to crest over the top of the Preston Avenue Bridge at more than 43 feet.

Six years later, during the Great Houston Flood of 1935, the city basically shut down after storms bombarded the Houston Ship Channel and downtown, turning 25 city blocks into a lake and causing an unheard-of $3 million in damages.

In response — and echoing similar flood-control projects throughout the country — the Corps of Engineers finished constructing the Barker Dam and Watershed (which sits on the south side of I-10) in 1945 and the Addicks Dam and Watershed (located on the north side of I-10) in 1948. The once mighty fail-safes, two of Harris County's 22 watersheds, were originally able to protect Houston from a 1,000-year flood.

The urbanization of West Houston — which doesn't seem like it's letting up anytime soon — can be seen from the top of the Barker levee while looking north towards I-10. Dunbar, Merz and residents of the area are concerned that the Grand Parkway will coax more development, which could send more storm-water runoff to the Barker Reservoir, pictured on the left.
Daniel Kramer
The urbanization of West Houston — which doesn't seem like it's letting up anytime soon — can be seen from the top of the Barker levee while looking north towards I-10. Dunbar, Merz and residents of the area are concerned that the Grand Parkway will coax more development, which could send more storm-water runoff to the Barker Reservoir, pictured on the left.
Lawrence Dunbar, a licensed professional engineer and former leader of the Corps of Engineers' flood control and reservoir regulation section, says that it might not take another Allison or Ike to bury Houston in billions of dollars in damage.
Lisa Ramirez
Lawrence Dunbar, a licensed professional engineer and former leader of the Corps of Engineers' flood control and reservoir regulation section, says that it might not take another Allison or Ike to bury Houston in billions of dollars in damage.

However, the U-shaped, earthen dams have deteriorated because of an increased presence of stored water behind the structures, a consequence of more residential and commercial properties in what has become — or is becoming — urban West Houston and Katy.

Addicks and Barker have also been weakened due to the natural decline of dams that are made out of a big pile of dirt. According to a 2010 study released by the United States Society on Dams, soil and rocks that have been used in dam construction tend to deform, erode and lose strength over time. (Other nationwide Level I dams that need hole-plugging include two reservoirs upstream of Nashville, Tennessee, one in Piedmont, Missouri, and the Success Dam in California's Central Valley.)

As a result, Houston's most valuable and proven flood-control mechanisms might not be able to protect the city against a 25-year storm event, says Lawrence Dunbar, a former head of the Army Corps of Engineers' flood control and reservoir regulation section in Chicago.

Unlike Allison and Ike, which beat down upon east and northeast Harris County, the bursts of rain on April 27 and 28, 2009, did a number on the west side of town — Addicks Reservoir rose to just two inches short of its previous high, or the equivalent of a 25-year event. During the weather event that the Harris County Flood Control District later called "extreme," the Corps observed leakage in the dams, which are constructed with outfit pipes (known as culverts) and a gate that can be opened so that water can escape from the reservoir.

"The Corps isn't quite sure how these voids got formed. Therefore, they're not sure if you get another big rain and the reservoir fills up again, even if it doesn't get high as it got before, they're not sure it can hold and voids won't form again," says Dunbar, a licensed professional engineer in Texas since 1983.

In the 1980s, the Corps installed concrete walls inside the earthen part of the dam to discourage leakage. However, the concrete wasn't installed above or below the culverts, which need replacing in the worst way.

"That's where they found these voids — under the culverts," says Dunbar. "What happens when a void forms is, it can basically let water blow through under the culverts or through the dam. When that happens, it's bad and dam failure is imminent. It's a big concern," says Dunbar.

In the meantime, the Corps is trying to win approval of an improvement proposal for Addicks and Barker dams. Ricky Villagomez, the Corps' Galveston District Project Manager, says a plan of action will be on the table in October; if approved, the three-year construction project would begin in October 2014. Even after the upgrades, the targeted lifespan of the reinforced dams tops out at 50 years.
_____________________

For the Corps of Engineers to slap a dam with a skull-and-crossbones-type Level I designation, two criteria have to be met: What's the likelihood the dam will fail? And if the dam were to collapse into rubble, what would be the consequences in terms of economic damage and dead people?

After the 2009 deluge, the Corps of Engineers' Dam Safety Action Classification risk number for Addicks and Barker shot from an "urgent" Level II rating (which had been determined by the Corps in 2005) to the "urgent and compelling" Level I. Under the Corps' classification, Level I means that immediate action must be taken to avoid dam failure.

"From going to a II to a I, the consequences didn't change. The risk of failure must have increased," says Dunbar. "The Corps tried to downplay the Level I tag, but that's their designation. They're the ones that raised it to Level I, but then they said there's not an imminent danger of failure?"

"The Corps admits that the consequence of a failure is 'catastrophic,'" adds Dunbar. "It's unacceptable."

Evelyn Merz, conservation chair of the Lone Star Chapter and the Houston Regional Group of the Sierra Club, agrees that the Corps hasn't been upfront to home and business owners who could be S.O.L. In fact, says Merz, she stumbled upon the information while researching Sierra Club v. Federal Emergency Management Agency, a court case that concerns flood insurance maps for Cypress Creek-area residents.

« Previous Page
 |
 
1
 
2
 
3
 
4
 
All
 
Next Page »
 
My Voice Nation Help
13 comments
stit60
stit60

LOL!  I always enjoy these apocolyptic weather articles yall do.  Makes me laugh, makes me worry and makes me think.  WHAT IF???  Holy shhhhh.  Okay.  I'm in Mission Bend---close.  I'm goin' to Home Depot RIGHT FRIGGIN NOW and buy some wood.  Time to build an ark!

red.marcy.rand
red.marcy.rand

More leftist apocalyptic alarmism ! The sky is falling ! Govmint must come to the rescue !

Can you believe that we folks out here in San Fransicko don't give a fiddler's fart what happens to Houston ?

turtletxn
turtletxn

Allison did not "destroy" 90 of 105 buildings on the University of Houston campus....

There is a giant difference in a building being flooded and/or damaged and a building being "destroyed."

For the record, call me a "nitpicker" but I quit reading the article at this point.

H_e_x
H_e_x

Too bad they can't fix thee dam. Too many trees to cut down for bike paths that already exist. 

tlafaver
tlafaver

It is difficult to believe much of this when it is infused with such hyperbolic statements; like water up to the tenth floor of buildings in the Energy Coriddor, and 90 of 105 buildings on UH campus destroyed during TS Allison. Get your facts straight!

Inthedamsshadow
Inthedamsshadow

Before claiming that 99 percent of the people in West Houston are not aware of the current situation, you might try actually coming out and speaking with some of the residents beyond simply those who are involved in the lawsuit. Most of my neighbors are hyper sensitive to the issues, including those concerning the City's efforts to destroy our forests to gain a paltry (but politically expedient from a Memorial super neighborhood perspective) 110 acre feet of water detention. The most important part of the story is left out - what are Congressmen Culberson, McCaul, Green, Paul and Olson doing to get funding and approval for not only upgrading the dams, but also for the Clodine Regional Detention Basin? What are Harris County and Fort Bend County doing to encourage the Congressmen to fund the dam upgrades and the development of the Clodine Regional Detention Basin? What are any of our elected officials doing to encourage the construction of a new reservoir northwest of the Addicks Reservoir? Our Mayor seems to think water stops at the City of Houston boundaries and she does nothing to work with other government entities responsible for water being fed into Buffalo Bayou from beyond. This story is larger and more complex than just the dams. See www.briarforestsn.org for some additional information. By the way, there were four meetings put on by the Corps, not just one (and they were all very well attended by our residents). Just because the local media does not question us or report our concerns does not mean we are ignorant to the issues.

1967warren
1967warren

here is just a reminder for all the newcomers to houston. google alvin or friendswood on july 25 and 26 1979. the N.W.S. weather station in alvin recorded over 42" of rain in 24hrs. yea that's right! for the few that lived in this,we will never forget and we have a good laugh when we read about these projected events based on just a few inches and what they could do to houston, ha. wait for the big one, it has happened before and will happen again some where

lovemadjc
lovemadjc

wow! i worry bout storms and heavy rains but to know we can be wiped out from this dam....when is this going to be a problem when were all gone?

Shummel67
Shummel67

I believe most taxpayers would be willing to fund a worthy project like this. We are unwilling to continue funding the waste that is rampant in all forms of government. I believe the City of Houston just received a grant to do some "improvements" along Buffalo Bayou like install a public shower?

Anse
Anse

If a psychic has an office out there and hasn't packed it up and left, then what in the heck are we worrying about?

nitpicker
nitpicker

I believe Barker's on the north of I-10 and Addicks on the south. "nitpicker"

ypman
ypman

The government has been playing a game of chance when it comes to dams for years. One only needs to visit the site of the Teton Dam collapse in Idaho for proof. While the USACE may say the problem is not really imminent they also can't say it will not happen soon. Then again part of the problem is also taxpayers unwilling to pay any additional taxes to make improvements to the nations aging infrastructure.

Interested Bystander
Interested Bystander

"thud against upper-floor windows of an Energy Corridor office tower" is pretty hyperbolic since a 10 story building would be over 100' high. Would be a enormous stetch to get water that high. However it might wash away 2nd Baptist on Voss away so al might not be so bad.

 
Loading...