DALLAS - Testing the Trinity River levees will cost at least $29 million and delay the Trinity River toll road by at least 20 months, Mayor Tom Leppert will tell the Dallas City Council today.
On March 31, the aging earthen dikes that protect downtown Dallas flunked an inspection by the U.S. Army Corps of Engineers, whose engineers said they no longer could be sure the levees would withstand a flood equal to the 1990 Trinity River flood. To find out for sure, the city would need to conduct extensive evaluations.
That extensive testing will cost at least $29 million and take until spring 2012.
"Experts will take about 1,500 boring samples - along the entire 23 miles of the levee system," Leppert will tell the council, according to prepared remarks distributed by city officials in advance of a press conference today with U.S. Sen. Kay Bailey Hutchison, R-Texas, and Rep. Eddie Bernice Johnson, D-Dallas. "Each boring sample costs about $8,600. So you can begin to see just how meticulous the process will be."
The mayor said the City Council will be asked on June 10 to approve spending $29 million for the study "to determine the items that need to be addressed - and what's needed to fix those items."
Dallas' finances are already in trouble, given the recession and sagging sales tax receipts. It was not immediately clear how the council will find the money needed to pay for the study - much less the far greater amount that might be required to fix whatever flaws are revealed.
The system study, as the exploration is being called, "will also identify any necessary remediation efforts for the 100-year and 800-year flood events. Funding will be identified and responsibility assigned to the city or a combination of the corps and the city."
Once the cost of the fixes is determined, the full cost could grow much larger, though the materials provided by the city suggest that the corps will credit at least half of the money the city spends on the study toward improvements.
"The bottom line and the news today is that we have solutions and a way to move forward," the mayor is expected to say. "Clearly there are costs and impacts to the project associated with the solutions."
The mayor also is expected to say: "Let me be clear about the impacts to the project's timeline: Our goal is to complete all study work by spring 2012, which will allow for construction activities to begin. Meeting this goal means that the construction for the Dallas floodway would be delayed by about 10 months while the Trinity Parkway construction would be delayed by 20 months.
"This is an extremely aggressive schedule, and it will take all the agencies working closely together and hitting all the intermediate deadlines to make."
The tollway will be delayed because "we have to determine through engineering analysis the correct fixes for the levees," according to the comments.