This audio is automatically generated. Please let us know if you have any comments.
Dive brief:
- Second phase of the Houma Navigation Canal Lock Complex opened on Aug. 7, according to a news release from the Louisiana Coastal Protection and Restoration Authority. Louisiana-based Thibodaux SeaLevel Construction is building the project, which has a cost of 300 million dollars.
- The HNC Lock complex is a navigation, flood barrier, and hydrologic restoration effort that will help limit saltwater intrusion and distribute freshwater in the Terrebonne Basin, southwest of New Orleans, and protect thousands of ‘hectares of wetland wildlife habitat, according to the release. It is also intended to facilitate commercial vessel travel in the Houma Navigation Channel.
- The new lockout will close one of the few remaining $6.6 billion gaps Morganza in the Gulf Hurricane Protection Systemwhich stretches 98 miles and uses levees, sluices and locks to protect approximately 200,000 residents and nearly 2,000 square miles of land in Terrebonne and Lafourche parishes from storm surge.
Diving knowledge:
The HNC Lock complex will span 110 feet wide and 800 feet long with sector gates on both sides, directly adjacent to the existing 250-foot-wide Bubba Dove barge lock, according to the release. A reinforced floodwall will link the two components across the canal and work together to allow larger ships to pass through the canal.
The project work includes the construction of doors in the inner and side sector of the bay and the lock chamber. It also involves the completion of the operations area, the control building and the access bridge to the control building, as well as the hydraulic dredging of approximately 135,000 cubic meters of material from the HNC to restore 15 acres of brackish marsh habitat.
“Today’s innovation brings us one step closer to completing the Morganza system in the Gulf and improving protection from hurricanes and other major storms for the residents of Terrebonne and Lafourche parishes,” said CPRA President Gordon Dove .
The first phase, completed in 2022, dredged 1 million cubic meters of material and built 150 acres of marsh in the areas surrounding the complex. A BP Oil Spill Restoration Act grant is partially funding the project.
Once completed, the Morganza Gulf Hurricane Protection System aims to provide a 100-year flood risk reduction, protecting the region from a storm surge which has a 1% chance of occurring in a given year, according to the project’s website. Last week, the Army Corps of Engineers announced it was beginning a full environmental review of the project to see if further improvements are needed to account for rising sea levels and the increased effects of storms, which could increase their costs.
