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
- All operating bridges in Louisiana guard VHF Channel 13. The locks found within the state guard either channel 14 or channel 13.
- The U.S. Coast Guard advises all vessels to exercise caution in any area where the GICW intersects major shipping channels. A “Security Call” on VHF channel 13 is requested prior to crossing any shipping channels, especially during periods of restricted visibility.
Found along the shores of the Louisiana Intracoastal Waterway
Bridges, Locks, & Overhead Power Lines
Bridges
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 | |
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 | ||
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/Gibbstown 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 2020. 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
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 | 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.
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.
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.
