Locks and Dams

IHNC Lock In Need Of Another Extended Closure

The New Orleans Engineer District has announced a necessary 30- to 60-day closure of the Inner Harbor Navigation Canal (IHNC) Lock in New Orleans for emergency repairs to the 97-year-old structure.

Vic Landry, Gulf Intracoastal Waterway and Bonnet Carré Spillway operations manager for the U.S. Army Corps of Engineers New Orleans District, said scouring, sinkholes and voids around and under the lock chamber have prompted the closure, tentatively scheduled for late summer or early fall.

“Last year, during high water, it got real bad where we were having these sinkholes forming around the lock chamber,” Landry said. “The sinkholes are definitely related to high water, and somehow we’re having water infiltration around the concrete chamber—It’s 100-year-old concrete.”

Landry said Corps officials aren’t certain where the infiltration is occurring, but they think it’s where the walls meet the floor of the lock. However, he didn’t rule out leaks in any vertical or horizontal joints in the centenarian concrete.

“The only way to address it is to do a dewatering, investigate and repair all these voids and the damaged concrete joints,” Landry said. “We don’t know how big it is, and we won’t know until we actually get it in an unwatered, dry condition.”

Talk of closure at IHNC will conjure memories of 2016 in the minds of operators on the Gulf Intracoastal Waterway (GIWW). That’s the last time IHNC, the sole gateway between the eastern and western reaches of the GIWW, was dewatered for an extended time. During that 112-day closure, industry leaders and the Gulf Intracoastal Canal Association (GICA) partnered with the Corps, the U.S. Coast Guard and the National Oceanic and Atmospheric Administration (NOAA) to shift transit between New Orleans and Gulfport, Miss., down the Mississippi River, through Baptiste Collette and across the Chandeleur Sound. Called the “Chandeleur Sound Alternate Route,” the route allowed navigation to continue along the GIWW, though the transit added time and distance to the usual route. While in service, NOAA issued daily weather reports for the open water reach between Baptiste Collette and Gulfport, and the Coast Guard placed both physical and virtual aids to navigation along the route.

GICA also hosted a Facebook group where towing vessel crews could share realtime conditions to help crews plan safe transits.

“I’ve been talking with the Coast Guard about reactivating the alternate route,” Landry said. “It’s fresh in everyone’s mind, so I think we can reactivate it pretty seamlessly.”

Landry said the New Orleans District just completed dredging Baptiste Collette, an east-facing outlet of the Mississippi River below Venice, La.

“The good thing is we have plenty of draft now,” Landry said. “As long as the river doesn’t drop a tremendous amount of sediment, we should be good and not require additional dredging.”

GICA President Jim Stark tied the successful implementation of the alternate route in 2016 to communication across the board.

“I’d say one of the greatest takeaways was the early coordination among all of the stakeholders and partners—it was a key to that success,” Stark said. “We started talking with Corps, Coast Guard and NOAA for surveying, weather and AToNs, and coordinating with the Captain of the Port to make sure we had all the regulatory issues resolved. Then we socialized that among our members to ensure they understood the safe operating parameters. All of that worked out well.”

Stark said talks with federal partners and industry representatives are already underway to “dust off” the alternate route plan for implementation later this year.

Stark and Landry both emphasized how the closure—and the impact it will have on commercial navigation—highlights how critical the IHNC Lock is to the nation’s economy and to flood and storm protection for the New Orleans area.

“We’ve been advocating for a safer, more resilient, more reliable lock for decades,” Stark said. “This just highlights that criticality. From our standpoint, it really would improve commerce. From the local populace’s standpoint, it would make that whole area safer. We won’t have as many barges waiting on lock turn [with a new lock]. We won’t have the inherent dangers of an almost 100-year-old lock and the failures that may come with that.”

For years, representatives from the New Orleans Engineer District have described IHNC as in an “active state of failure.” Landry said that’s still a very accurate description.

“We’re looking at a relic, and it is in a state of failure,” he said. “We’re trying to minimize the risk associated with that failure. This old lock presents tremendous challenges.”

Besides serving as a navigation structure, the Inner Harbor Navigation Canal Lock serves as part of the New Orleans region’s perimeter protection system against both river flooding and hurricane-related storm surge.

“It’s like a levee or a floodwall,” Landry said. “If we had the lock compromised or any stability compromised—it’s a critical component in the whole risk reduction system, so if that would fail, it would be catastrophic.”

As yet, though, the New Orleans District doesn’t have the funds to conduct the dewatering and repair work at IHNC later this year. Landry said he has applied for emergency funding from the 1 percent of the Corps’ annual budget set aside for emergencies.

Landry said he hopes to hear back within a week or two whether that emergency funding request will be approved.