The Texas portion of the Gulf Intracoastal Waterway (GIWW/GICW) has its start at 30°03.2’ N / 93°43.2’ W (MM 266.0 WHL) on the Sabine River which divides Texas from Louisiana.
From the Sabine River, the Texas GIWW runs for 415.5 miles starting out in a generally southwesterly direction before gradually turning to the south near Aransas, TX before ending in Brownsville, TX at 25°57.1’ N / 97°24.1’ W (MM "681.5 WHL") very near the Texas / Mexico border.
Navigation
Buoyage
The Texas Gulf Intracoastal Waterway is marked with your standard Aids to Navigation which also display yellow triangles or yellow squares. When southwest and south bound along the Texas GICW, 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 Sabine River, Galveston Bay, Chocolate Bay, Port O’Conner, Victoria Barge Canal, and Port Isabel where the GIWW intersects or coincides with the channels marked by the Lateral Buoyage System.
NOAA chart coverage of the Texas portion of the GIWW beginning at (MM “266.0 WHL”) to (MM “681.5 WHL” is provided by charts #11331, #11324, #11322, #11319, #11315, 11314, 11308, 11306, 11303, and #11302. These charts can be viewed by clicking on the links below:
Chart #11331 covers the GIWW from Ellender, LA at (MM "243.6 WHL") to Galveston Bay at (MM "350.2 WHL").
Chart #11324 covers the GIWW from Galveston Bay Entrance at (MM "350.2 WHL") to West Bay at (MM "359.9 WHL").
Chart ##11322 covers the GIWW from Galveston Bay at (MM "359.9 WHL") to Cedar Lakes at (MM "409.2 WHL").
Chart ##11319 covers the GIWW from Cedar Lakes at (MM "409.2 WHL") to Espiritu Santo Bay at (MM "479.5 WHL").
Chart #11315 covers the GIWW from Espiritu Santo Bay at (MM "479.5 WHL") to Carlos Bay at (MM "510.5 WHL").
Chart #11314 covers the GIWW from Carlos Bay at (MM "510.5 WHL") to Redfish Bay at (MM "535.5 WHL").
Chart 11308 covers the GIWW from Redfish Bay at (MM "535.5 WHL") to Laguna Madre at (MM "587.3 WHL").
Chart 11306 covers covers the GIWW from Laguna Madre at (MM "535.5 WHL") to Chubby Island at (MM "635.1 WHL").
Chart 11303 covers the GIWW from Chubby Island at (MM "635.1 WHL") to Stover Point at (MM "656.9 WHL").
Chart 11302 covers the GIWW from Stover Point at (MM "656.9 WHL") to Port of Brownsville at (MM "681.5 WHL").
All distances along the Texas 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 Louisiana State line and the Mexican border is measured based on increasing mileage West of Harvey Lock from (MM “266.0 WHL”) to (MM "681.5 WHL").
Channels
The Federal project depth for the Texas 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 and locks in Texas guard VHF Channel 13.
The U.S. Coast Guard advises all vessels to exercise caution in any area where the GIWW 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
Bridges
A total of 13 bridges cross the Gulf Intracoastal Waterway in the state of Texas. The fixed bridges (10), all have vertical clearances of 73’ or better with the exception of the "State Road 361 Bridge" in Aransas Pass, TX having a clearance of only 48’. An alternate channel does exist that allows this bridge to be bypassed if necessary.
The (3) operating bridges all have closed vertical clearances between 0’ and 8’ that will prohibit most vessels from passing through without an opening. All guard VHF Channel 13.
The table below lists the bridges, their schedules, and restrictions along the Texas Gulf Intracoastal Waterway from the Sabine River in Texas southwest to the Mexican Border.
This list is believed to be accurate as of
July 2024.
If any errors or omissions are noted, please e-mail us at
with any corrections or recommendations.
Gulf Intracoastal Waterway Bridges - Texas (GIWW)
Port Arthur to Freeport
Mile Marker
Bridge
Charted Vert. Clear.
Schedule
Restrictions
VHF
287.7 WHL
Gulf Gate Bridge
136’
Fixed Bridge
289.0 WHL
West Port Arthur Bridge
73’
Fixed Bridge
319.3 WHL
High Island Bridge
73’
Fixed Bridge
357.5 WHL
Galveston Causeway RR Lift Bridge
8’ / 73’
Opens on Demand
13
357.6 WHL
Gulf Freeway Bridge
73’
Fixed Bridge
393.8 WHL
Surfside Beach Bridge
73’
Fixed Bridge
Gulf Intracoastal Waterway Bridges - Texas (GIWW)
Freeport to Brownsville
Mile Marker
Bridge
Charted Vert. Clear.
Schedule
Restrictions
VHF
397.6 WHL
Freeport/Bryan Beach Bridge
73’
Fixed Bridge
418.0 WHL
Sargent Beach Pontoon Bridge
4’
Opens on Demand
Small Boat Passage
13
440.7 WHL
Market Street Bridge
73’
Fixed Bridge
533.5 WHL
SR 361 Bridge
48’
Fixed Bridge
552.7 WHL
JFK Causeway Bridge
73’
Fixed Bridge
665.1 WHL
Queen Isabella Bridge
73’
Fixed Bridge
666.0
Port Isabel/Long Island Pontoon Bridge
0’
Opens on Demand
13
The above table can be downloaded for your personal and private use. They list the bridges, their schedules, and restrictions in statute miles, nautical miles, and kilometers along the Texas segment of the Intracoastal Waterway from the Sabine River in Texas southwest to the Mexican Border.
Numerous overhead cables cross the Texas Gulf Intracoastal Waterway. The minimum authorized clearance of overhead cables crossing the GIWW is 61 feet and is also found at Aransas Pass, TX at (MM 533.1 WHL.)
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 the Texas coast. Under normal conditions the mean range of tide averages about less than 1.5’ at Sabine Pass to about 0.5’ at Port O’Conner and across the remainder of the state to Port Isabel.
Texas typically experiences a "Mixed Tide" - exhibiting (2) unequal high and low tides each day.
Texas Entrances, Inlets, and Passes
At last count, in January 2020, there were 15 entrances, inlets, or passes found along the Texas coastline. From Sabin Pass at the Louisiana/Texas Border southwest to the Rio Grande River at the Texas/Mexican Border.
While all of these inlets provide access to sheltered waters, many are dangerously shallow that should not be attempted without local knowledge. All provide direct access to the Gulf Intracoastal Waterway. We have listed them on the next page along with useful information on each to aid you in deciding if you wish to use a particular inlet.