Gulf Intracoastal Waterway

The Gulf Intracoastal Waterway (GIWW) is the portion of the Intracoastal Waterway located along the Gulf Coast of the United States. It is a navigable inland waterway running approximately 1300 mi from Saint Marks, Florida, to Brownsville, Texas.

The waterway provides a channel with a controlling depth of 12 ft, designed primarily for barge transportation. Although the U.S. government proposals for such a waterway were made in the early 19th century, the Gulf Intracoastal Waterway was not completed until 1949.

EHL & WHL mileages
Locations along the Gulf Intracoastal Waterway are defined in terms of statute miles (as opposed to nautical miles, in which most marine routes are measured) east and west of Harvey Lock, a navigation lock in the New Orleans area located at 29.909°N, -90.084°W. The Hathaway Bridge in Panama City, Florida, for example, is at mile 284.6 EHL (East of Harvey Lock). The Queen Isabella Causeway Bridge at South Padre Island is at mile 665.1 WHL (West of Harvey Lock).

Connecting waterways
The Gulf Intracoastal Waterway crosses or meets, and in some cases is confluent with, numerous other navigable rivers and waterways. They include:


 * Apalachicola River
 * Arroyo Colorado
 * Atchafalaya River
 * Bayou Lafourche
 * Bayou Terrebonne
 * Calcasieu River
 * Calcasieu Ship Channel
 * Delcambre Canal
 * Houston Ship Channel
 * Industrial Canal
 * Lower Mississippi River
 * Mississippi River-Gulf Outlet Canal
 * Mobile Bay (connecting to the Tenn-Tom Waterway)
 * Pearl River
 * Sabine-Neches Waterway (Includes portions of)
 * Neches River
 * Sabine Lake
 * Sabine River
 * Santa Rosa Sound
 * The Rigolets
 * Vermilion River

Ports and harbors
Many of the busiest ports in the United States in terms of tons of cargo are located on or near the Gulf Intracoastal Waterway. Notable ports on or near the waterway include: Florida Alabama Mississippi Louisiana Texas
 * Apalachicola, Florida
 * Carrabelle, Florida
 * Panama City, Florida
 * Pensacola, Florida
 * Mobile, Alabama - Ranked 11th busiest
 * Gulfport, Mississippi
 * Pascagoula, Mississippi - Ranked 29th busiest
 * Baton Rouge, Louisiana - Ranked 7th busiest
 * Houma, Louisiana -
 * Intracoastal City, Louisiana
 * Lake Charles, Louisiana - Ranked 14th busiest
 * Larose, Louisiana
 * Morgan City, Louisiana
 * New Orleans, Louisiana - Ranked 5th busiest
 * Port Allen, Louisiana
 * Port of South Louisiana - Ranked 2nd busiest
 * Port of Plaquemines - Ranked 12th busiest
 * Beaumont, Texas - Ranked 8th busiest
 * Brownsville, Texas
 * Corpus Christi, Texas - Ranked 3rd busiest
 * Port Freeport, Texas - Ranked 16th busiest
 * Galveston, Texas - Ranked 46th busiest
 * Houston, Texas - Ranked as busiest port in the United States
 * Port Arthur, Texas - Ranked 15th busiest
 * Port Lavaca - Point Comfort, Texas
 * Texas City, Texas - Ranked 20th busiest
 * Victoria, Texas