Locks and Dams

Corps Proposes Reconfiguration Of GIWW Structures

Industry and community groups are weighing in on the U.S. Army Corps of Engineers’ tentatively selected plan for reconfiguring the Brazos River Floodgates and the Colorado River Locks, both located along the Gulf Intracoastal Waterway on the Texas Gulf Coast between Galveston and Corpus Christi.

The Corps released its feasibility study and the tentatively selected plan (TSP) for the project back in February, with a public meeting held March 13 in West Columbia, Texas, to discuss the proposal. The public comment period for the project goes through April 11.

For the Brazos River crossing, the Corps proposes removing the existing floodgates on the west side of the river and creating “a minimum 125-foot open channel” there, while constructing a new, wider set of floodgates on the east side. The new set of 125-foot floodgates would be set back some 1,000 feet from the east side of the river to help mitigate the difficult passage for vessels on the Gulf Intracoastal Waterway (GIWW) crossing the Brazos.

The Colorado River crossing of the GIWW features two pairs of floodgates: two “riverside” gates and two outer floodgates. The tentatively selected plan calls for removing the interior, riverside gates, while only rehabilitating the 75-foot-wide outer gates. The navigation channel between the remaining floodgates would widen to 125 feet.

The total initial cost for the plan is estimated at just over $184.6 million. The Corps estimates two years to complete the work at Brazos, “if adequate funding is provided.” For the Colorado River portion of the project, the Corps estimates a more expeditious 15-month construction timeline, again with the disclaimer “if adequate funding is provided.” The Texas Department of Transportation is the non-federal sponsor, and 50 percent of the cost would be paid for by the Inland Waterways Trust Fund.

The Gulf Intracoastal Canal Association (GICA), which represents companies doing business on and transiting the GIWW, offered its general support for the Brazos River component of the plan.

“Removing the west floodgate, significantly increasing the size of the east forebay by moving the east gate further east in the GIWW, and widening the east gate to 125 feet are certain to result in safer, more efficient towboat and barge operations,” GICA President Jim Stark said in a letter commenting on the feasibility study. “With these modifications, we can expect fewer costly accidents and fewer delays than we experience with the present configuration. Additionally, our towboat operators would like to see an easing of the severe turning angle to make transits across the river even safer; I understand the study team plans to include this work as it works to refine the TSP.”

There were local concerns over the Brazos proposal, though. To the east, representatives from the Freeport area expressed concern that widening the gates on the east side to 125 feet would increase flows down the GIWW from the Brazos, resulting in increased sedimentation in the Freeport Channel.

On the west side of the Brazos, the group Friends of the River San Bernard sharply criticized the plan for not taking into account the opening of the mouth of the San Bernard River, which crosses the GIWW just west of the Brazos. The mouth of the San Bernard River is currently silted in, but funds stemming from BP/Deepwater Horizon oil spill penalties have been allocated to dredge the mouth of the San Bernard.

“In the public comment meeting last month in West Columbia, the Corps representatives for the gates/locks project, who are out of the New Orleans office, seemed totally unaware the Bernard mouth will be opened in the next year or so,” said Tom Ronayne, a spokesman for Friends of the River San Bernard. “All of their modeling assumed the mouth would be closed.”

Ronayne said that, with its mouth dredged, the San Bernard becomes a saltwater ecosystem that passes floods relatively quickly and easily. He fears that, with the west side of the Brazos flowing freely into the GIWW, the San Bernard will quickly silt in again and reconvert to a fresh water system.

“The [GIWW] was never intended to provide the Brazos with additional Gulf outlets through the Port of Freeport and the mouths of the San Bernard and Caney Creek,” Ronayne said. “The structures at the Brazos and Colorado Rivers were designed and built to keep the flood waters of those rivers within their respective channels.

“Those structures are now old, difficult to maintain, and in need of replacement,” he continued. “We certainly understand the budget pressure on the Corps, but that doesn’t justify eliminating three of the six structures and ignoring the consequences.”

Stark, who attended the May 13 meeting in West Columbia, said in the official GICA statement that, while his organization would support continued study at Brazos, the financial burden of mitigating sedimentation at the San Bernard River or the Freeport Channel should not be borne by the maritime industry.

“GICA understands these concerns and would support additional examination of alternatives that reduce Freeport Channel silting and continue to provide sufficient flow on the San Bernard River to keep the mouth open at the Gulf of Mexico,” Stark’s statement said. “However, that examination appears to be outside the scope of the primary objective of this study—to improve navigability of the GIWW at the crossing of the Brazos and Colorado rivers. Likewise, any additional project costs associated with alternatives focusing on silt reduction and river flows on the San Bernard should not be cost-shared with the Inland Waterways Trust Fund.”

With regard to the Colorado River proposal, Stark said he would like the Corps to consider installing 125-foot-wide gates, rather than rehabilitating the existing 75-foot-wide gates.

“We strongly feel that, to make it safe and to make it more efficient, they would need to be widened to 125 feet,” Stark said.

Stark pointed out that, with the standard width of a modern tank barge at 54 feet, maintaining 75-foot-wide gates at Colorado will require multiple trips through the gates, which carries risk.

“We feel strongly that gate size is important to us,” Stark said. “It saves having to conduct so many trips through for anything greater than a one-barge tow.”

To conclude his letter, Stark pledged, “GICA understands that widening the existing 75-foot gates to a preferred 125 feet means additional construction costs. Our members will continue to work with the study team to refine and monetize the benefits associated with the wider gates.”

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