Dallas may face a new obstacle in getting the proposed Trinity River toll road built between the river's aging levees.
The levees – 39-foot-high earthen walls running 11.5 miles along each side of the river – may simply be too old and too "historic" under federal law to allow the road to be built where the city wants it.
The U.S. Army Corps of Engineers is considering whether the levees – indeed the whole floodway, complete with six pumping stations and even the river channel itself – are deserving of federal protection as a single "historic property."
State and federal officials say such a determination would not by itself kick the toll road out of the levees.
But they said it would be a significant obstacle for the city to overcome. Kevin Craig, the corps project manager for the Trinity River project, said Monday that his agency has not decided what position it will take.
It's not clear when it will make a final determination.
But in a 55-page research paper produced in November by the corps, it cited the levees' historical importance to the development of modern Dallas and noted that the levees are considered a man-made landmark by the American Society of Civil Engineers.
It argued that a previous analysis by the Texas Department of Transportation that concluded the levees were not historic property had been flawed.
Dallas officials have scoffed at the idea that the Trinity's earthen dams deserve historic protection.
But officially, Mayor Tom Leppert was more measured in his remarks.
"While the levee system has historical significance for Dallas, the city does not feel the levees' structure meets the standard for historic designation," Leppert said in a statement to The Dallas Morning News on Monday. "Improvements and repairs have been made continually over the decades. ... And clearly, there are plenty of new improvements, repairs and opportunities for the levees in the future, including the addition of another two feet in height to boost flood safety.
The levees' history is constantly in motion which should clearly disqualify it for historic designation."
If the levees do receive the extra federal protection, it could make it more difficult for the Federal Highway Administration to select the route for the proposed toll road favored by the city, a spokesman for the U.S. Department of Transportation said Monday.
Spokesman Doug Hecox noted that the U.S. Department of Transportation Act forbids spending federal funds on a highway project that harms a historic property – unless there is no "feasible or prudent alternative."
"The corps is not subject to 4(f), but federally funded transportation projects are," he said, referring to the relevant section of the DOT Act. "Once we have reviewed the corps' study, we will be in a better position to evaluate the applicability of 4(f) to any of the alternatives for this proposed project.'"
Currently, the highway administration is evaluating a number of possible routes for the toll road, including some that run between the levees and some outside the levees. The city prefers a route between the levees in part because the most likely option outside the levees would require condemning hundreds of parcels of property along Riverfront Drive.
Several factors are involved in determining whether an alternative highway route would be "prudent," including: whether it "results in unacceptable and severe adverse social, economic or other environmental impacts," whether it "would cause extraordinary community disruption," or "it has additional construction costs of an extraordinary magnitude," according to language in the act.
Adrienne Campbell, who reviews state and federal highway projects' impact on historic properties for the Texas Historical Commission, said federal rules are much stricter on highway projects than on most other federally supported projects.
"It becomes a much bigger deal for the FHWA than for the corps," Campbell said. "FHWA has to comply with section 4(f) of the Department of Transportation Act. That says, if you can avoid impacting a historic property, then you have to choose another alternative. 4(f) has a lot more teeth."
The National Historic Preservation Act requires agencies to avoid, modify or mitigate any harmful effects a project may have on historic properties.
Typically, that's easily done.
When the corps determined the levees near Fort Worth were historic properties, improvement projects were not halted. Nor has work on two pumping stations by Dallas been halted, despite the fact that the corps has determined the two stations were historic.
But highway projects are different.
Aware of that, the Texas Department of Transportation, acting as an agent for the federal highway agency, evaluated the levees years ago to determine if they were eligible to be considered historic properties, and decided they were not. The Texas Historical Commission concurred with that decision in 2002.
But last year, when the state Transportation Department asked the commission to make a similar determination – namely, that for purposes of the federal Trinity River toll road environmental study the levees were not a historic property – the commission said it could not do so until the corps completes its own review.
The corps, it said in a letter to TxDOT, has raised legitimate concerns that the previous determinations had been incomplete.
Hecox, the spokesman for the Department of Transportation in Washington, said the corps review of the Trinity River project is intimately entwined with the highway agency's review of the Trinity Parkway, so the corps' decision on the eligibility of the levees for historic status is important.
"The FHWA is waiting for the results of the historic property survey and evaluation being conducted by the [corps] and will review it upon receipt," Hecox said.
"The two agencies anticipate making a joint recommendation on eligibility at that time."
That's when the Texas Historical Commission will decide whether it concurs, as well.
But if the two agencies disagree, the path forward gets murkier.
Campbell said the dispute could rise to the top levels of both the highway administration and the corps, and ultimately be resolved by a federal official called the Keeper of the National Register of Historic Places at the National Parks Service.
"Both agencies have indicated a concern over the potential for derailment of the environmental process," Campbell's boss, State Historic Preservation Officer Mark Wolfe, wrote in his letter to TxDOT.
Hecox said the corps and the federal transportation agency will work to avoid a prolonged disagreement.