LMR Dredging Update 316

The U.S. Army Corps of Engineers (USACE) has two cutterhead dredges and two hopper dredges under contract for channel maintenance on the Mississippi River Ship Channel in the area of Southwest Pass. Manson Construction confirmed that their hopper dredge GLENN EDWARDS is expected to commence dredging in Southwest Pass this Friday, March 20, 2020.  The USACE now confirms the government hopper dredge WHEELER is expected to commence dredging in Southwest Pass on Wednesday, March 25, 2020.  The most deficient reaches of the Ship Channel according to the latest surveys are at Cubits Gap, the Head of Passes and on the jetty end of Southwest Pass.


The Bar Pilots and Federal Pilots reduced their maximum draft recommendation to 42 feet (freshwater) on February 1, 2020.  This maximum draft restriction remains in place for all vessels transiting Southwest Pass and represents the controlling draft for the Mississippi River Ship Channel.  Pilots continue to report extensive shoaling after the last crest of 17.08 feet on the Carrollton Gauge at 0800 hours on March 7, 2020.  Long range forecasts indicate a slow fall from 15.2 feet (today) to 13.5 feet on April 12, 2020 although forecasts for future precipitation levels across the Mississippi River Basin indicate the potential for another rise.

The Crescent River Port Pilots Association’s maximum freshwater draft of 46 feet remains in effect as implemented on February 7, 2020.  The Crescent Pilots reduction is based on shoaling in their route in the area of Cubits Gap.


NEWPORT: The hopper dredge NEWPORT (Manson Construction) continues dredging on assignment at the Head of Passes (Mile 0.5 Above Head of Passes [AHP] to Mile 0.5 Below Head of Passes [BHP]).  The hopper dredge is working under the Gulf Coast Regional Hopper Dredge Contract 2020.  This is the first utilization of the Regional contract which allows a hopper dredge to respond to shoaling across channels in both the Mobile and New Orleans USACE Districts.  The NEWPORT began dredging under the first Gulf Coast Regional Hopper Dredge Contract 2020 on February 1, 2020.

GLENN EDWARDS: The Southwest Pass Hopper Dredge Rental Contract #13-2019 was awarded to Manson Construction.  The hopper dredge BAYPORT was expected to respond to this contract.  However, the BAYPORT has been delayed in the shipyard and the GLENN EDWARDS will respond to this contract and is expected to start dredging in Southwest Pass on Friday (March 20, 2020).


WHEELER: The USACE’s hopper dredge WHEELER is expected to begin dredging in Southwest Pass by March 25th under Readiness Exercise #1-2020 after completing shipyard repairs.


E.W. ELLEFSEN:  The cutterhead dredge E.W. ELLEFSEN (Weeks Marine) is expected to commence dredging in the area of the West Bay Diversion later today on assignment from Mile 4.7 AHP to Mile 2.5 AHP (western side).  The cutterhead completed the previous assignment from Mile 2.5 BHP to Mile 3.4 BHP on Saturday, March 14, 2020 and moved upriver. The cutterhead dredge began dredging in SWP on February 4, 2020.

CAPTAIN FRANK: Weeks Marine’s cutterhead dredge CAPTAIN FRANK is dredging at Mile 7.2 BHP and working on assignment from Mile 6.8 BHP to Mile 8.2 BHP on the eastern side of the channel.  The cutterhead commenced dredging in Southwest Pass on January 24, 2020 under Southwest Pass Cutterhead Dredge Rental Contract #3-2019.


E.W. ELLEFSEN:  The cutterhead dredge E.W. ELLEFSEN (Weeks Marine) will return to the HDDA project to beneficially place material in the Pass A’ Loutre Wildlife Management Area (PALWMA) upon completion of the emergency dredging in SWP.  The cutterhead was scheduled to perform dredging in the HDDA but is being utilized to respond to the emergency channel conditions on the Ship Channel first.  The cutterhead dredges have already beneficially utilized approximately 13 mcy of material from the HDDA and restored roughly 1,040 acres.  When this project is completed later this year, approximately 1,200 acres will have been restored in the PALWMA.

The Carrollton Gauge (New Orleans) reading at 1000 hours today was 15.23 feet, with a 24-hour change of – 0.12 feet.

There are multiple reaches of the channel that are deficient and based on past experience there is sufficient material to justify up to three additional hopper dredges.  The arrival of the GLENN EDWARDS and the WHEELER are critical to maintaining and/or restoring the deficient channel. 

The latest forecasts predict the Carrollton Gauge will continue a slow fall although there is increased variability in forecasts based on future precipitation levels. Note the upward trend in the 16 Day QPF from NOAA above.