Gulf Intracoastal Waterway - Louisiana Route Segment
Lake Borgne, LA to Sabine River, LA
Louisiana’s section of the Gulf Intracoastal Waterway (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 GICW 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.
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 GICW intersects or coincides with the channels marked by the Lateral Buoyage System.
NOAA chart coverage of this portion of the GICW 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 GICW 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").
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.
- 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.
Bridges, Locks, & Overhead Power Lines
GICW - Louisiana Bridge Schedule
Louisiana Gulf Intracoastal Waterway Bridges
|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||Inner Harbor Lift Bridge||40’/156’||Opens on Demand||Closed 0630-0830 & 1530-1745 Mon.-Fri. Excl. Federal Holidays.||13|
|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|
|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|
|35.2 WHL||SR 308 Bridge||73’||Fixed Bridge|
|35.6 WHL||5th Street Lift Bridge||35’||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|
|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|
|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. 0600-0800 and 1400-1600.||13|
|243.8 WHL||Ellender Lift Bridge||50’||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 January 2017. 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.
GICW - Louisiana Lock Schedule
Louisiana Gulf Intracoastal Waterway Locks
|Mile Marker||Bridge||Charted Vert. Clear.||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.
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.
Inlets & Passes
There are more than (31) Passes (Inlets) between the Gulf of Mexico and the inside waters of Louisiana. Most of these are only suitable for shallow draft vessels or local knowledge, but some can be considered navigable by most vessels.
Chef Menteur Pass
Chef Menteur Pass, a pass between Lake Borgne and Lake Pontchartrain also intersects the GICW at (MM "22.9 EHL") about 1.7 miles above the entrance. While the pass itself is deep with good water almost bank to bank, the seaward approach to the pass has a least depth of 6 feet. A new Gulf Intracoastal Waterway alignment channel crosses Chef Menteur Pass 1 mile SE of the original Intracoastal Waterway crossing.
Southwest Pass, the westernmost of the passes for the Mississippi River. The entrance has jetties on both sides with the East Jetty marked by the Southwest Pass Entrance Light (Fl 10s) and is equipped with a RACON showing (-‧-). The approach channel to Southwest Pass is marked by a lighted buoy Mo (a), 1.6 miles south of the entrance.
Southwest Pass is deep and well-marked by daybeacons and ranges to the Head of Passes. Above the Head of Passes the channel is marked both by daybeacons and a few buoys, but with few exceptions deep water is available bank to bank.
Intersection with the Gulf Intracoastal Waterway happens abeam of the Inner Harbor Navigation Canal 112.6 miles above the entrance.
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 15’ 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 GICW 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 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.