LMR Dredging Update 032320

The U.S. Army Corps of Engineers (USACE) has two industry cutterhead dredges and two industry hopper dredges working to recover the Mississippi River Ship Channel in the area of Southwest Pass. The government hopper dredge WHEELER is now expected to commence dredging in Southwest Pass on Friday, March 27, 2020 under Red Flag Emergency Call Out #1-2020.  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.  The maximum draft restriction of 42 feet freshwater remains in place for all vessels transiting Southwest Pass and represents the controlling draft for the Mississippi River Ship Channel. 

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 mainly in the area of Cubits Gap.

Long range forecasts have been adjusted to show the stage levels on the Carrollton Gauge remaining steady at approximately 14.85  (today) rising to 15 feet and slowly increasing to 15.5 feet in early to mid-April.  However, future precipitation levels across the Mississippi River Basin indicate the potential for another rise over the next two weeks


GLENN EDWARDS: The GLENN EDWARDS (Manson Construction) commenced dredging on assignment at the Head of Passes (Mile 1.2 Above Head of Passes [AHP] to Mile 1.0 Below Head of Passes [BHP]) under Southwest Pass Hopper Dredge Rental Contract #13-2019 on March 20,2020.  The GLENN EDWARDS is presently working in the area of Cubits Gap as the cutterhead dredge E.W. ELLEFSEN is undergoing minor repairs, when the cutterhead resumes dredging the GLENN EDWARDS will return to the assignment at the Head of Passes.

NEWPORT: The hopper dredge NEWPORT (Manson Construction) is dredging on assignment on the Jetty End of SWP (Mile 18.2 BHP to Mile 19.5 BHP).  The NEWPORT is dredging 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.  


WHEELER: The USACE’s hopper dredge WHEELER is expected to begin dredging in Southwest Pass on March 27th after the shipyard repairs are certified.  The WHEELER’s usage will be under Red Flag Emergency Callout #1-2020 as approved for 60 days of work in response to not receiving any bids to Southwest Pass Hopper Dredge Rental Contract #2-2020 (February 6, 2020).


E.W. ELLEFSEN:  The cutterhead dredge E.W. ELLEFSEN (Weeks Marine) is undergoing repairs that are expected to be complete over the next 24-hours.  The dredge will resume dredging at Mile 4.29 AHP in the area of the West Bay Diversion on assignment from Mile 4.5 AHP to Mile 2.7 AHP (western side).  The cutterhead dredge began dredging in SWP on February 4, 2020 utilizing hours left over from New Orleans Harbor Cutterhead Dredge Rental Contract #3-2019.

CAPTAIN FRANK: Weeks Marine’s cutterhead dredge CAPTAIN FRANK is dredging at Mile 7.45 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 0900 hours today was 14.85 feet, with a 24-hour change of + 0.18 feet.

There are multiple reaches of the channel that are deficient and the arrival of the GLENN EDWARDS and the WHEELER are critical to maintaining and/or restoring the deficient channel.

The graph below is reproduced from NOAA’s National Weather Service website and represents an experimental product to account for the complexity of accurately predicting long-range precipitation.  This forecast projects stage levels based on expected precipitation for 2 days (top) and 16 days (bottom) and was developed within the North American Ensemble Forecast System (NAEFS) computer model and highlights Quantitative Precipitation Forecasts (QPF).  Along with the forecasts, a shaded area is also provided to indicate uncertainty for the forecast each day in the future.   These plots are experimental and not an official forecast product.