Officials break ground on the Houma Navigation Canal (HNC) Lock Complex

Earlier this month, Gov. John Bel Edwards and Louisiana Coastal Protection and Restoration Authority (CPRA), along with other local and state officials, held a sod turning ceremony to celebrate the start of construction on the Houma Navigation Canal (HNC) Lock Complex.

During the ceremony, which was held on Monday, November 8, officials also announced the completion of the Grand Bayou Floodgate, two critical components of the Morganza to the Gulf Hurricane Protection System.

The Morganza-to-the-Gulf Hurricane Protection System is a levee, lock, and floodgate system designed to provide 100-year, Category 3 storm surge protection to more than 150,000 Americans living in coastal Terrebonne and Lafourche Parishes (60 miles southwest of New Orleans) as well as over 1,700 square miles of fresh and saltwater marsh.

With the completion of the 147-foot Grand Bayou Floodgate, the Morganza to the Gulf system now has a continuous levee segment stretching 47 miles from Grand Bayou in Lafourche Parish to upper Bayou Dularge in Terrebonne Parish to prevent floodwaters from impacting the region.

“Here we are announcing two substantial advances in our efforts to provide Terrebonne and Lafourche parishes with 100-year storm surge protection,” commented Gov. Edwards. “The new Floodgate, combined with HNC Lock Complex, are game-changers for the entire Morganza to the Gulf system.”

“The road to strengthening the Morganza to the Gulf system and providing the Bayou Region with upgraded hurricane protection has been paved by hard work and collaboration with parish governments and levee districts,” said CPRA Chairman Chip Kline. “We’re thrilled to announce such meaningful progress toward our shared goal of providing a safer and better protected future for those in Terrebonne and Lafourche parishes.”

Phase 1 of the HNC Lock Complex project will dredge over 1 million cubic yards of material to prepare the area for the lock complex and create 178 acres of marsh in six areas north of the complex along the navigation channel. According to CPRA, Phase 1 is anticipated to be complete in the fall of 2022.

The HNC Lock will allow a longer window of opportunity for navigation activities when the adjacent Bubba Dove Floodgate is closed to protect communities from storm surge or high water events. During gate closures, the lock will allow vessels to travel in either direction on the HNC, enabling officials to close the floodgate earlier and keep it closed longer, benefiting the area’s ecosystem suffering from saltwater intrusion.

Terrebonne Parish President Gordon “Gordy” Dove and Lafourche Parish President Archie Chaisson joined the Governor for the announcements and praised the projects for enhancing the Morganza to the Gulf system’s hurricane protection capabilities.

“The Grand Bayou Floodgate is a critical link in the Morganza to the Gulf Hurricane Protection system,” said Dove. “The HNC Lock complex is a companion piece to the ‘Bubba Dove’ Floodgate, and will allow marine traffic to effectively bypass the floodgate when it’s required to be closed to protect against storm surge and saltwater intrusion.”

“The new Grand Bayou Floodgate is another tool to help protect our residents and I’m glad to see construction being completed,” stated Chaisson. “This culminates the work of a lot of agencies over many years and will help protect our residents for years to come.”

The HNC Lock Complex, worth approx.$350 million, is a joint effort of CPRA and the Terrebonne Levee and Conservation District. A tentative bid date for construction of Phase 2 of the lock structure, which will include an 800-foot lock chamber with 110-foot-wide sector gates, is anticipated in spring 2022.

Engineering, design, and construction for Phases 1 and 2 of the HNC Lock Complex are funded with money resulting from the damages of the Deepwater Horizon oil spill, allocated through the Resources and Ecosystems Sustainability, Tourist Opportunities, and Revived Economies of the Gulf Coast States Act (RESTORE Act).

“As a native of Pointe-aux-Chenes, a small rural two parish community on the Terrebonne-Lafourche boundary, I am very appreciative of our partners in getting this done. Additionally, the beginning of construction of the HNC Lock Complex is a huge landmark in our efforts for hurricane protection and maintaining sustainable coastal communities,” said Terrebonne Levee and Conservation District Executive Director Reggie Dupre.

In 2014, then CPRA Chairman Garret Graves, CPRA Executive Director Jerome Zeringue, State Sen. Norby Chabert, and State Rep. Gordon Dove led the charge to use Deepwater Horizon oil spill funds to build the HNC Lock Complex under the direction of CPRA and the Terrebonne Levee District.

“Our design consultants were able to optimize the Corps’ design of the Lock Complex to provide significant cost savings and a reduction of wetland impacts. The Lock Complex is a perfect example of why we created CPRA in the aftermath of Hurricane Katrina; a true integration of coastal restoration and hurricane protection,” concluded Dupre.

Sealevel Construction, Inc., headquartered in Thibodaux, won the competitively bid dredging contract for the lock site, as well as the contract for construction of the Grand Bayou Floodgate and Receiving Structure.