Lower Mississippi River (LMR) Dredging Update 102919

LMR Dredging Update 102919.pdf

The Corps of Engineers Mississippi Valley New Orleans (MVN) continues dredging operations in response to record shoaling deposited by historic long-term high river stages (record flood event created by record precipitation levels). The MVN continues to recover authorized channel dimensions on the Crossings Above New Orleans and in Southwest Pass. All three dustpan dredges are working on the Crossings and a hopper dredge is presently working on the channel in Southwest Pass.  A newly christened cutterhead dredge is expected to resume dredging in SWP later this week.

 

DUSTPAN DREDGE(S) ON THE CROSSINGS ABOVE NEW ORLEANS:

 HURLEY: The Corps dustpan dredge HURLEY continues dredging full channel dimensions (500 feet by 45 feet) at Red Eye Crossing (Mile 224 Above Head of Passes [AHP]). The government dustpan dredge originally commenced dredging on the Crossings on May 4, 2019.

 WALLCE McGEORGE: The industry dustpan dredge WALLCE McGEORGE continues dredging full channel dimensions at Alhambra Crossing (Mile 192 AHP). The industry dustpan dredge commenced dredging on the Crossings on May 9, 2019.

While the WALLACE McGEORGE is dredging at Alhambra Crossing the White Castle Anchorage (Mile 191.1 AHP to Mile 190.4 AHP) will be off limits for vessel usage. The NOBRA and Federal Pilots will keep the White Castle Anchorage cleared of vessels until dredging operations are completed.  The estimated date of completion at Alhambra is November 7, 2019. 

JADWIN: The Corps dustpan dredge completed dredging full channel dimensions at Belmont Crossing (Mile 154 AHP) earlier this morning.  The dustpan dredge will be moving upriver to start an assignment on full channel dimensions at Smoke Bend (Mile 175 AHP).  The dredge must undergo minor repairs first but is expected to commence dredging at Smoke Bend by tomorrow evening (Wednesday, October 30, 2019).

 

HOPPER DREDGE(S) IN THE SOUTHWEST PASS (SWP):

NEWPORT:  The industry hopper dredge NEWPORT (Manson Construction) continues dredging at the Head of Passes (Mile 1 AHP to Mile 1 Below Head of Passes [BHP]) on the eastern side of the channel.  The NEWPORT is dredging under Southwest Pass Hopper Dredge Rental Contract #8-2019 and is expected to remain on the Ship Channel until mid-November (2019).

 

CUTTERHEAD DREDGE(S) IN SOUTHWEST PASS (SWP):

 J.S. CHATRY: Weeks Marine’s new cutterhead dredge J.S. CHATRY will be basically replacing both of the cutterheads that have been working in SWP.  The J.S. CHATRY will begin dredging on Thursday, October 31, 2019 by taking over the assignment at the Head of Passes that was being worked by the C.R. McCASKILL (Mile 3.5 AHP to Mile 0 [Head of Passes]).  The R.S. WEEKS has departed the Hopper Dredge Disposal Area and will eventually be replaced by the J.S. CHATRY after it completes the channel assignment at the Head of Passes.

 C.R. McCASKILL:  Weeks Marine’s cutterhead dredge C.R. McCASKILL was relieved by the J.S. CHATRY on assignment from Cubits Gap (Mile 3.5 AHP) to the Head of Passes (Mile 0) on the western side of the channel.  The cutterhead began dredging on July 24, 2019 under Southwest Pass Cutterhead Dredge Rental Contract #2-2019.

 

CUTTERHEAD DREDGE(S) IN THE HOPPER DREDGE DISPOSAL AREA (HDDA):

R.S. WEEKS: The industry cutterhead dredge R.S. WEEKS (Weeks Marine) has departed the HDDA and the contract is presently idle.  The J.S. CHATRY will resume work on the HDDA contract after completion of the Head of Passes assignment.  All material will be beneficially used in the Pass A’Loutre Wildlife Management Area (PALWMA).  The MVN was recently able to extend this contract, the original contract was to remove 12 million cubic yards (mcy) of material from the HDDA. An increase in funding was utilized to extend this contract and increase the amount of material to be removed by approximately 3.0 mcy, increasing the contract to remove a total of 15.3 mcy of material.  The cutterhead dredges have now beneficially utilized more than 10.5 mcy of material from the HDDA and restored approximately 840 acres in the PALWMA.

The Carrollton Gauge (New Orleans) reading at 1500 hours today was 7.55 feet, with a 24-hour change of + 0.18 feet.

 

The Baton Rouge Gauge reading at 0800 hours today was 22.87 feet, with a 24-hour change of + 0.43 feet.

  

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.

NORL1_67_28d_forecast_error_plot.png