Safety Alert: Atchafalaya River

1. The Atchafalaya River gauge has reached and is forecasted to remain above 3.0 feet. In accordance with 33 Code of Federal Regulations (CFR) 165.811, the following High-Water restrictions are in place for the designated regulated navigation area (RNA) that encompasses the Atchafalaya River in the vicinity of the Morgan City Triple Span Bridges (the bridges), including the waters extending 2000 yds north of the Highway 90 Bridge and 4000 yds south of the Morgan City Railroad Bridge (MCRRB). For these restrictions, length of tow (LoT) indicates length and width of the barges, excluding length of towing vessel.

a. Towing on a hawser is not authorized, except that one self-propelled vessel may tow one other vessel without barges NORTHBOUND.

b. Max length of tow remains 1,180 feet when transiting the bridges.

c. Max length of double wide tows is 70 feet wide and 600 feet long when transiting the bridges.

d. Tows with a loaded box in the lead must not exceed 600 feet in length. Tows with an empty box in the lead must not exceed 1,180 feet.

e. Minimal available horsepower requirements in accordance with 33 CFR TABLE 165.811(e) are in effect, and are as follows:

TANDEM TOWS: Minimum Available Horsepower Requirements [The greater value listed]

DOUBLE WIDE TOWS (>54ft): Minimum Available Horsepower Requirements [The lesser value listed]

TANDEM TOWS: Minimum Available Horsepower Requirements [The greater value listed]
Direction of Tow	Day (sunrise to sunset)	Night (sunset to sunrise)
Upbound	400 hp or 3 x (LoT-300 ft)	600 hp or 3 x (LoT-200 ft)
Downbound	600 hp or 3 x (LoT-200 ft)	600 hp or 3 x (LoT)

 

DOUBLE WIDE TOWS (>54ft): Minimum Available Horsepower Requirements [The lesser value listed]
Direction of Tow	Day (sunrise to sunset)	Night (sunset to sunrise)
Upbound	1800 hp or 3 x LoT	2400 hp or 3 x LoT
Downbound	2400 hp or 3 x LoT	3000 hp or 3 x LoT

f. A 5% variance from the available horsepower is authorized.

g. Towing Certain Dangerous Cargoes (CDC) Barges, as defined in 33 CFR 160.202, shall have available horsepower of at least 600, or three times the length of tow, whichever is greater.

h. Use of Assist Boats to Meet Required Horsepower Criteria: North and Southbound tandem tows shall have at least 50% of the required horsepower wired-in when transiting the bridges. Once that condition is met, an assist boat may be used to make up the remaining horsepower deficit. North and Southbound doublewide tows shall have at least 75% of the required horsepower wired-in when transiting the bridges. Once that condition is met, an assist boat may be used to make up the remaining horsepower deficit.

i. To comply with this requirement, tows must ensure the assist boat is ready, and in position to provide IMMEDIATE assistance throughout the entire transit through the Regulated Navigation Area (RNA).

j. Mariners shall use extreme caution when transiting the Wax Lake Outlet due to high abeam currents. All mariners unfamiliar with this transit should consider using an assist vessel.

2. Navigating vessels in high water conditions increases the risk of casualties. Mariners are reminded of their ongoing responsibility to conduct and manage their required navigation assessments and voyage plans to prepare bridge teams for encountering known hazards. Vessel operators are strongly encouraged to continuously evaluate the experience of their mariners operating in high water conditions and consider ensuring more experienced wheelmen are on watch during critical stages of the voyage or using “posted” wheelmen to transit through high-risk areas.

3. For further information on this advisory contact VTS Berwick Bay at (985) 380-3240 or via radio on channel 11 VHF-FM.

 

4. For the VTS Berwick Bay User Manual and complete list of current MSIBs within the COTP Houma Zone visit: https://homeport.uscg.mil/port-directory/houma

//signed//

T. O’Brien
Captain, U.S. Coast Guard
Captain of the Port
Houma, Louisiana