Chron Editorial Board

Let’s address Houston’s dams

Jay Blazek Crossley, Oct 04, 11.

Tagged with sprawl, roads, flooding, dam, induced development

In the grip of the most intense dry spell in the city’s history, with the annual rainfall nearly two feet below normal, worries about walls of water racing down Buffalo Bayou into the heart of Houston might seem far-fetched. However, that’s a scenario raised in a 2010 U.S. Army Corps of Engineers study of the Addicks and Barker dams to the west of Houston. It found that the compacted earth structures are among the highest at-risk dams in the United States, and reclassified their status as “Urgent and Compelling.”

It states that Addicks and Barker are among dams whose progression toward failure under normal operations is almost certain from immediately to within a few years without intervention. Interim safety measures already taken include limiting reservoir levels by doubling permissible flow rates into Buffalo Bayou and pumping support material into the dams’ foundations.

The environmental group Sierra Club has seized on the status of the dams in opposing the recently approved construction plans for a segment of the Grand Parkway that would run through the Katy Prairie area northwest of the Addicks and Barker. The lawyer for the group, Jim Blackburn, argues that the construction of Segment E of the parkway and development of adjacent property would increase drainage into the reservoirs during flooding periods and exacerbate the already existing threat to the dams, which were built to alleviate Buffalo Bayou flooding that battered downtown Houston in the early 20th century.

The Texas Department of Transportation recently set aside $350 million for the toll road project. The Army Corps of Engineers has issued a permit for the work and determined it would not have unacceptable impacts on the Addicks and Barker reservoirs.

Blackburn claims the conclusion is undermined by internal Corps of Engineers email from its hydrology branch indicating both Segment E and subsequent development of the prairie area would have a negative impact. According to Blackburn, the documents focus on the threat to the dams from large pools of water that persist for lengthy periods of time and undermine the earthen structures.

The Sierra Club is calling for further study of the problem before construction commences on the Grand Parkway segment. The group has filed a lawsuit to force a re-evaluation of the impact of the project on runoff into the Addicks-Barker watershed.

Full Story: Let’s address Houston’s dam problem
Source: Houston Chronicle, October 2, 2011

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