Collapse raises concerns about Trinity levee integrity



Posted on December 1, 2009 at 3:33 AM

Updated Tuesday, Dec 1 at 2:29 PM

DALLAS — A section of the Trinity River levee has collapsed, and that is raising new concerns about the integrity of the system that shields the city from flood waters.

The collapse is just off Interstate 35E at Regal Row.

City of Dallas officials say that unlike most levee collapses they see, this one was caused by a water leak.

A Dallas Water Utilities water line runs across the top of the Trinity River levee where the collapse occurred; a slow leak caused the erosion leading to the damage.

"This is a unique situation, obviously," said Kelly High of Trinity Watershed Management. "You've got a water line that's running near the levee, and so you've got a leak, and that's pretty unique and rare."

Earlier this year, the U.S. Army Corps of Engineers gave the city a failing grade on an important inspection, halting work on key elements of the city's largest-ever public works project.

The Corps has concerns about trees planted along the Trinity River toll road, worries about overgrown vegetation, and fears that the soil composition could spell disaster.

"I know that they have concerns about the utility crossings in the levees, and so I know Water Utilities has a pretty aggressive inspection program," High said. "I think this line was probably tested back in 2007-2008, but since then it has developed a leak."

City officials say this is the third levee collapse in recent weeks. There are two others in the upper west levees, blamed on wet weather that saturated the ground.

Rain in the forecast could delay efforts by workers to shore up the levee breeches.