The U.S. Army Corps of Engineers (USACE) continues working to restore authorized channel dimensions along the Mississippi River Ship Channel (MRSC). The USACE has recently requested that the owners of the three identified obstructions in the Venice Corridor provide new surveys to document accurate depths over the two pipelines and utility cable. The lack of accurate survey data for the three remaining obstructions will continue to delay the mechanically deepened channel being opened up to deeper vessel traffic. The channel deepening effort now depends on accurate depth of cover surveys over these three lines, accurate depth of cover surveys would provide integrity to the maximum draft decision-making process. The dustpan dredges are currently working to maintain full authorized channel dimensions on the Crossings (45 feet deep by 500 feet wide). The USACE expects to commence Phase 2 of the MRSC deepening to 50 feet at Fairview Crossing (Mile 115 Above Head of Passes [AHP]) by early November (2021). The USACE noted that the start of Phase 2 of the deepening was delayed by the impact of Hurricane Ida on the Ship Channel.
DUSTPAN DREDGES WORKING ON THE CROSSINGS ABOVE NEW ORLEANS:
WALLACE McGEORGE: The industry dustpan dredge WALLACE McGEORGE continues dredging full channel dimensions (500 feet) at Red Eye Crossing (Mile 224 AHP). The dustpan began dredging on the Crossings on May 20, 2021.
JADWIN: The government dustpan dredge JADWIN continues dredging operations at Philadelphia Crossing (Mile 183 AHP). The dustpan commenced dredging full channel dimensions at Philadelphia Crossing at 1800 hours on September 14, 2021. The JADWIN began work on the Crossings on June 24 (2021).
CUTTERHEAD DREDGE(S) IN THE HOPPER DREDGE DISPOSAL AREA (HDDA):
ILLINOIS: The cutterhead dredge ILLINOIS (Great Lakes Dredge and Dock) completed work under Hopper Dredge Disposal Area Cutterhead Rental Contract #1-2019 on September 10, 2021. The submerged dredge pipeline was successfully extracted during refloating operations yesterday, Sunday, September 19, 2021. GLDD has some additional equipment to remove but no additional channel closures or expected. The tentative backup closure date for tomorrow has been cancelled.
The ILLINOIS removed and beneficially utilized approximately 12.0 million cubic yards (mcy) of material from the HDDA. The Coalition estimates the 12 mcy would restore approximately 1,000 acres of new land in the environmentally sensitive birds-foot delta within the West Bay Receiving Area (Below Venice, LA).
MISSISSIPPI RIVER SHIP CHANNEL DEEPENING PHASE 1:
The USACE completed the Phase 1 dredging for the historic project to deepen the Mississippi River Ship Channel (MRSC) to 50 feet on May 7, 2021. The Phase 1 section of the Ship Channel extends from Venice at Mile 13 AHP to Mile 22 Below Head of Passes. The Big River Coalition is actively working with the USACE to identify advanced hydrographic survey equipment and techniques that can be used to provide accurate “depth of cover” survey data over these obstructions. This data will be utilized in the informed decision-making process as deeper draft recommendations are made based on the acquirement of accurate survey data over these documented obstructions. The USACE mechanically deepened the Ship Channel from Venice to the Gulf of Mexico through the dredge contracts detailed below in Phase 1 of the historic river deepening project:
Southwest Pass Cutterhead Dredge Rental Contract #1-2020: was awarded to Weeks Marine on August 20, 2020. This contract was completed by the cutterhead dredges CAPTAIN FRANK that dredged from September 11, 2020 until March 3, 2021 and the E.W. ELLEFSEN that dredged from November 18, 2020 until March 19, 2021.
Southwest Pass Cutterhead Dredge Rental Contract #2-2020: was awarded to Manson Construction on August 27, 2020. The cutterhead dredge ROBERT M. WHITE dredged under this contract from October 23, 2020 until completion on March 18, 2021.
Southwest Pass Hopper Dredge Rental Contract #9-2020: was awarded to Manson Construction on September 21, 2020. The GLENN EDWARDS worked under this deepening contract from January 14, 2021 until completion on May 7, 2021.
MISSISSIPPI RIVER SHIP CHANNEL DEEPENING PHASE 2:
The USACE recently meet with representatives from pilot associations and navigation stakeholders to formalize a revised logistical approach to the Phase 2 MRSC deepening operations. The adjusted Phase 2 assignments will deepen the four southernmost (downriver) of the Crossings Above New Orleans, a reach of the Ship Channel from Smoke Bend (Mile 175 AHP) to Fairview Crossing (Mile 115 AHP). The USACE now expects to begin Phase 2 of the Ship Channel deepening project to 50 feet in early November (2021). The deepening will begin at Fairview and then work upriver to the next three Crossings: Belmont [Mile 154 AHP]; Rich Bend [Mile 158 AHP] and Smoke Bend [Mile 175 AHP]. The Phase 2 dredging operations will deepen a reach of the Ship Channel extending a few miles above New Orleans to an area near Donaldsonville (Louisiana). The Phase 2 dredging assignments to deepen the Ship Channel will be accomplished by the utilization of both dustpan and hopper dredges.
MISSISSIPPI RIVER STAGE UPDATES:
The Carrollton Gauge (New Orleans) reading at 1100 hours today was 4.16 feet with a 24-hour change of – 0.33 feet. The National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service Extended Streamflow Prediction (28-Day) for the Carrollton Gauge issued today forecasts stages will slowly fall to approximately 3.0 feet on September 25 and then fluctuate about that same level with a fall to 2.5 feet on October 18 (2021). The highest crest recorded on the Carrollton Gauge in 2021 to date is 15.44 feet at 1700 hours on April 16, 2021. The Carrollton Gauge crest attributed to the precipitation and coastal storm surge from Hurricane Ida was recorded at 1400 hours on Sunday, August 29, 2021 with a reading of 11.36 feet.
The Baton Rouge Gauge reading at 1100 hours was 11.92 feet with a 24-hour change of – 0.82 feet. The National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service Extended Streamflow Prediction (28-Day) for the Baton Rouge Gauge issued today forecasts stages will slowly fall to 8.5 feet on September 26 and then rise to just over 10 feet in early October and begin a slow fall to 7.4 feet on October 18 (2021).