Cruising/Navigating the GIWW in Louisiana

Lake Borgne, LA to Sabine River, LA

Louisiana’s section of the Gulf Intracoastal Waterway (GIWW/GICW) begins near the mouth of the Pearl River, MS near (MM "41.0 EHL") at 30°15.042’ N / 88°23.666’ W in Lake Borgne.

From Lake Borgne, this section of the GIWW runs generally in a westerly direction for 307.0 miles ending at 30°03.2’ N / 93°43.2’ W (MM "266.0 WHL") on the Sabine River at the Texas state line.

Navigation

Buoyage

Louisiana’s GICW is marked with your standard Aids to Navigation which also display yellow triangles or yellow squares. When westbound along Louisiana’s Gulf Intracoastal Waterway, marks displaying yellow triangles should be kept on your starboard hand and those marked with yellow squares should be kept to port.


While typically the yellow triangles will be found on red markers and yellow squares are found on green markers, caution should be exercised along this route in the vicinity of the Mississippi River, Lower Atchafalaya River, Vermilion River, and Calcasieu River where the GIWW intersects or coincides with the channels marked by the Lateral Buoyage System.

Charts

NOAA chart coverage of this portion of the GIWW beginning at (MM “41.0 EHL”) to (MM "266.0 WHL" is provided by charts #11367, #11365, #11355, #11350, #11348, and #11331. These charts can be viewed by clicking on the links below:

Chart #11367 - Waveland to Catahoula Bay
Chart #11365 - Barataria and Bayou Lafourche Waterways
Chart #11355 - Catahoula Bay to Wax Lake Outlet
Chart #11350 - Wax Lake Outlet to Forked Island
Chart #11348 - Forked Island to Ellender
Chart #11331 - Ellender to Galveston Bay

Distances and Mileages

All distances along the Louisiana’s Gulf Intracoastal Waterway are given in statute miles unless otherwise noted. Statute miles are used in order to conform to the distances shown on the small craft charts typically used along this route.

This portion of the GIWW between the Mississippi State line and the Texas State line is measured based on both decreasing and increasing mileage East and West of Harvey Lock from (MM "41.0 EHL") to (MM "266.0 WHL").

Channels

The Federal project depth for the Louisiana portion of the Gulf Intracoastal Waterway provides for a minimum channel depth of 12 feet. Even though every effort is made to maintain the project depth, the actual controlling depths in the channels may vary due to shoaling reducing the available water depth until maintenance dredging can be accomplished.

Communications


Bridges, Locks, & Overhead Power Lines

Bridges

Open Down Arrow GIWW - Louisiana Bridge Schedule
The Rigolets to New Orleans

Gulf Intracoastal Waterway Bridges - Louisiana (GIWW)


The Rigolets to New Orleans

Mile Marker Bridge Charted Vert. Clear. Schedule Restrictions VHF
 
13.0 EHL Paris Road Bridge 137’ Fixed Bridge    
7.5 EHL Florida Avenue Lift Bridge 0’/156’ Opens on Demand Closed 0630-0830 & 1530-1745 Mon.-Fri. Excl. Federal Holidays. 13
6.7 EHL North Claiborne Lift Bridge 40’/156’ Opens on Demand Closed 0630-0830 & 1530-1745 Mon.-Fri. Excl. Federal Holidays. 13
6.5 EHL Inner Harbor/Industrail Lock   On Demand Passage in conjunction with adjacent bridge schedules. 14
6.2 EHL St. Claude Avenue Bascule Bridge 0’/70’ Opens on Demand Closed 0630-0830 & 1530-1745 Mon.-Fri. Excl. Federal Holidays. 13
2.5 EHL Crescent City Connector Bridge 150’ Fixed Bridges Twin Spans  

Open Down Arrow GIWW - Louisiana Bridge Schedule
New Orleans to Morgan City

Gulf Intracoastal Waterway Bridges - Louisiana (GIWW)


New Orleans to Morgan City

Mile Marker Bridge Charted Vert. Clear. Schedule Restrictions VHF
 
0.0 Harvey Lock   On Demand   14
0.1 WHL Union Pacific RR Bascule Bridge 7’ Opens on Demand   13
0.15 WHL 4th Street Bascule Bridge 7’ Opens on Demand   13
0.8 WHL West Bank Expressway 95’ Fixed Bridge Twin Spans  
2.8 WHL Lapalco Blvd. Bascule Bridge 45’ Opens on Demand Closed Mon.-Fri. 0630-0830 and from 1545-1745 except holidays. 09
11.9 WHL Crown Point Bridge 73’ Fixed Bridge    
35.0 WHL Larose Highway Bridge 73’ Fixed Bridge    
35.7 WHL 5th Street Lift Bridge 35’ / 73’ Opens on Demand   13
49.8 WHL Bayou Blue Road Pontoon Bridge 0’ Opens on Demand   13
54.4 WHL Prospect Blvd. Bridge 73’ Fixed Bridge    
57.6 WHL Park Avenue Bridge 73’ Fixed Bridge    
57.7 WHL Main Street Bridge 73’ Fixed Bridge    
59.9 WHL Bayou Dularge Bascule Bridge 40’ On Demand Closed Mon.-Fri. from 0630-0830, 1145-1215, 1245-1315 and from 1630-1800 except Fed. holidays. 13
93.0 WHL Bayou Boeuf Lock   On Demand   14

Open Down Arrow GIWW - Louisiana Bridge Schedule
Morgan City to Port Arthur

Gulf Intracoastal Waterway Bridges - Louisiana (GIWW)


Morgan City to Port Arthur

Mile Marker Bridge Charted Vert. Clear. Schedule Restrictions VHF
 
113.0 WHL North Bend Bridge 73’ Fixed Bridge    
134.0 WHL Louisa Bascule Bridge 73’ On Demand The draw shall open on signal if at least 24 hours notice is given. 13
163.0 WHL Leland-Bowman Lock   On Demand   14
170.3 WHL Forked Island Bridge 73’ Fixed Bridge    
219.8 WHL W. Creole Highway Bridge 73’ Fixed Bridge    
231.5 WHL Grand Lake Pontoon Bridge 0’ Opens on Demand   13
238.0 WHL Black Bayou Pontoon Bridge 0’ Opens on Demand Closed Mon-Fri 0600 to 0800 and 1400-1600. 13
238.2 WHL Calcasieu Lock   On Demand   14
243.8 WHL Ellender Lift Bridge 50’/135’ Opens on Demand (4 Hour notice required).   13

The table above lists the bridges, their schedules, and restrictions along Louisiana’s Gulf Intracoastal Waterway from the Pearl River in Louisiana west to the Texas State line.

This list is believed to be accurate as of July 2019. If any errors or omissions are noted, please e-mail us at with any corrections or recommendations.

This bridge operating schedule can be downloaded for your personal and private use as a ZIP file. The file contains the schedule in Adobe (.pdf) file format.

Louisiana Gulf Coast Bridge Schedule - Download

GICW/GIWW Bridge and Lock Schedule (Florida to Texas) - Download

Locks

Open Down Arrow GICW - Louisiana Lock Schedule

Louisiana Gulf Intracoastal Waterway Locks

Mile Marker Bridge   Schedule Restrictions VHF
6.5 EHL Inner Harbor Canal Lock   On Demand Operates within the operating times of the Florida Avenue, Claibourne, and St. Claude operating bridges. 14
0.0 Harvey Lock   On Demand   14
93.0 WHL Bayou Boeuf Lock   On Demand   14
163.0 WHL Leland-Bowman Lock   On Demand   14
238.2 WHL Calcasieu Lock   On Demand Lock will remain closed M-F 0700 to 1700 thru December 2019. Other times on Demand. 13

Overhead Power Lines

Quite a few overhead cables cross Louisiana’s Gulf Intracoastal Waterway. Numerous cable crossings with a minimum authorized clearance noted at 90’ are located between (MM "34.0 WHL") and (MM "135.0 WHL"). (1) overhead cable at (MM "219.9 WHL") has been reported to have a clearance of only 82’.

Caution - Many of the overhead cables over the waterway carry high voltage, and an extra margin of safety should be allowed when the weather is threatening.

Tides

Tidal ranges are fairly small along Louisiana’s coast. Under normal conditions the mean range of tide averages between less than 0.5’ at Chef Menteur Pass to about 0.5’ across the remainder of the state to the Texas State line.

Louisiana experiences (2) types of tides; from the Mississippi state line west to Vermilion Bay the type of tide experienced is commonly refered to as a "Diurnal Tide" - exhibiting (1) high tide and (1) low tide each day. West of Vermilion Bay to the Texas State Line, a "Mixed Tide" gradually takes over having (2) unequal high and low tides each day.

Entrances, Inlets, and Passes

There are literally hundreds of entrances, inlets, and passes between the Gulf of Mexico and the inside waters of Louisiana. Many only suitable for shallow draft vessels or local knowledge, but some can be considered navigable by most vessels. We are going to list only those that are important to accessing the Gulf Intracoastal waterway or that can be considered navigable for most vessels.

Open Down Arrow GIWW - Louisiana Entrances, Inlets, and Passes
The Rigolets to New Orleans

Chef Menteur Pass

Chef Menteur Pass, located 10.3 NM southwest of Rigolets Inlet. Provides access to the GIWW and Lake Pontchartrain.

The approach and entrance channel is marked by a lighted beacon (Fl R 4s 17ft 5M "2"). The approach is surrounded by shoals, but 6 feet can be carried with careful navigation and 5 feet can be carried over the shoals at most times.

Inside the pass, depths increase to 30+ feet mid-channel until reaching the Gulf Intracoastal Waterway. The pass is unmarked, but reportedly has good water nearly bank to bank.

Chef Menteur Pass intersects the GIWW 2.1 NM above the entrance marker at (MM "22.9 EHL") near lighted beacon (Fl R 2.5s 17ft 4M "4").

Cautions – A new Gulf Intracoastal Waterway alignment channel crosses Chef Menteur Pass 1 mile SSE of the original Intracoastal Waterway crossing, but reports are of shoaling to 3 feet. Caution is advised.

Southwest Pass

Southwest Pass, the westernmost of the passes for the Mississippi River and the only one capable of deep draft vessels. Besides the Mississippi River, the majority of the mid-west is accessible through this pass. From New Orleans, LA to the head of navigation in Minneapolis, MN.

The approach to Southwest Pass is marked by buoy (RW "SW" Mo (A) located at 28°52’39"N / 89°25’55"W), approximately 1.75 NM south of the entrance. Lighted buoys and ranges mark the approach.

Prominent on the approach is Southwest Pass Entrance Light (Fl 10s 122ft 12M at 28°54’21"N / 89°25’43"W) RACON equipped showing the Morse code equivalent of the letter "K" or (–·–).

The entrance has jetties on both sides with a range leading in. The channel through to the intersection with the Gulf Intracoastal Waterway and well above New Orleans is deep (45+ feet) with good water available bank to bank with few exceptions. It is well-marked by lighted buoys and lighted beacons.

Tides and Currents – The current, so far as is known, can be depended upon to set nearly straight out from between the jetties, but cross currents can be present due to winds and seas. Tidal range at the entrance is typically about 1 foot.

Intersection with the Gulf Intracoastal Waterway happens at a number of locations off the Mississippi River depending upon your direction of travel.

Algiers Navigation Canal Inlet

The Algiers Navigation Canal is located at MM "88.2 AHP": (97.8 NM above the Southwest Pass Entrance). It allows access to the GIWW when westbound. The canal has good water bank to bank and is crossed by (3) bridges, (1) fixed and (2) lift bridges. All bridges offer 100 feet of clearance.

The canal entrance is on the south side of the Mississippi River and intersects the GIWW at MM ("6.5 WHL" near lighted beacon (Fl (2+1) R 6s 20ft 3M).

Inner Harbor Navigation Canal

The Inner Harbor Navigation Canal entrance is on the north side of the Mississippi River and provides access to and is part of the Gulf Intracoastal Waterway. This inlet is for vessels eastbound on the GIWW.

The intersection with the GIWW takes place at MM "92.5": AHP located approximately 101.6 NM above the Southwest Pass Entrance or about 80.5 NM Above Head of Passes (AHP). The inlet is marked by (2) lighted beacons: Fl G 2.5s 30ft 4M "1" on the west side and Q R 40ft 4M "2" on the east side.

Cautions – When turning in from the Mississippi River, be aware of a stump awash (at 9.9 feet water level) about 10 feet out from the east bank.

Tides and Currents – Tides in this area are almost non-existent except at the lowest of Mississippi River Water Stages. Tidal currents likewise do not exist other than the currents due to the outflow of the river.

Harvey Canal

Located approximately 2.9 miles above the Crescent City Connector Bridges, it is marked by a traffic light to control entry. This canal is actually part of the Gulf Intracoastal Waterway with the Harvey Lock being MM "0.0." It marks the split between mileages measured East of Harvey Lock (EHL) and West of Harvey Lock (WHL).

The canal has good water bank to bank and is crossed by both bascule and fixed bridges with a minimum vertical clearance of 95 feet.

Open Down Arrow GIWW - Louisiana Entrances, Inlets, and Passes
New Orleans to Cameron

Cat Island Pass

Cat Island Pass is well marked with lighted buoys, daybeacons, and ranges. It has a controlling depth of 13’, but minimum depths of 10’ have been noted.

Cat Island Pass intersects the Houma Navigation Canal 1.5 miles above the entrance. From the Houma Navigation Canal, the least depth reported was 10’ to its intersection with the GIWW at Houma, LA at (MM “59.6 WHL”), 36.8 miles above Cat Island Pass.

Atchafalaya Bay Inlet

Atchafalaya Bay Inlet is located between Point au Fer Island to the west and Eugene Island to the west. It is deep (20’) and well-marked by buoys and daybeacons. Point au Fer Light is the most prominent navigation aid in the area.

From the entrance, a dredged channel leads to the Lower Atchafalaya River and on to its intersection with the Gulf Intracoastal Waterway at (MM “98.2 WHL”) 26.9 miles above the entrance.

Calcasieu Pass

Calcasieu Pass is a deep-draft channel leading to Lake Charles, LA. It is deep with a minimum controlling depth of 33’ and is well-marked with buoys, daybeacons and ranges. The entrance is protected by jetties. The approach channel is marked by a fairway buoy RW “CC” showing a Mo (A) white light.

Calcasieu Pass intersects the GICW at (MM “241.5 WHL”) 24 miles above the entrance.

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