Intracoastal Waterway

Intracoastal Waterway
Name	Intracoastal Waterway
Caption	A map showing the primary route of the Intracoastal Waterway along the Atlantic and Gulf coasts.
Length mi	~3,000
Start point	Manasquan River, New Jersey
End point	Brownsville, Texas
Date began	1919
Date completed	1949
Status	Operational
Governing body	United States Army Corps of Engineers

Intracoastal Waterway. The Intracoastal Waterway is a 3,000-mile network of navigable channels running along the Atlantic and Gulf of Mexico coasts of the United States. It provides a protected inland route for commercial and recreational vessels, shielding them from the hazards of the open ocean. The system is a vital piece of national infrastructure, managed primarily by the United States Army Corps of Engineers and connecting major ports from New Jersey to the Mexican border.

Overview

This extensive waterway comprises both natural bodies of water, such as sounds, bays, and rivers, and constructed elements like canals and dredged channels. It is formally divided into two main sections: the Atlantic Intracoastal Waterway and the Gulf Intracoastal Waterway. Key commercial ports like Norfolk, Virginia, Jacksonville, Florida, Houston, Texas, and New Orleans are integral nodes along its path. The system's primary legal authority stems from the Rivers and Harbors Act of 1919, which authorized its creation and continuous federal maintenance.

History

The concept of a protected coastal route dates to the early colonial era, with early proposals emerging after the American Revolutionary War. The Gallatin Report of 1808 by Secretary of the Treasury Albert Gallatin was a seminal early plan for national internal improvements. Construction of discrete segments began in the 19th century, notably with the Delaware and Raritan Canal and the Chesapeake and Delaware Canal. The modern, unified system was largely born from the 1919 Rivers and Harbors Act, with major construction efforts accelerating during the Great Depression and World War II, the latter highlighting its strategic military value for moving United States Navy and United States Merchant Marine vessels safely.

Route and description

The Atlantic section begins at the Manasquan River in New Jersey, traversing the Delaware Bay, the Chesapeake Bay, the Albemarle Sound, and the Indian River Lagoon before terminating at Miami, Florida. Notable artificial canals include the Cape Cod Canal in Massachusetts and the Okeechobee Waterway across Florida. The Gulf section commences at Fort Myers, Florida, proceeding through Tampa Bay, across the Panhandle of Florida, and along the coasts of Alabama, Mississippi, and Louisiana, before ending at Brownsville, Texas. Critical segments here include the Houston Ship Channel and the Gulf Intracoastal Waterway's path through the Mississippi River Delta.

Engineering and maintenance

The waterway is a massive feat of civil engineering, maintained to a minimum depth of twelve feet for most of its length, though some sections are deeper. Continuous maintenance dredging by the United States Army Corps of Engineers is required to combat siltation, particularly in areas like Georgia's marshes and the Mississippi River Delta. The system features numerous fixed-span and movable bridges, such as bascule and swing bridges, as well as locks like those at the Great Bridge, Virginia and the Inner Harbor Navigation Canal in New Orleans. Funding and authorization for these projects are governed by periodic Water Resources Development Act legislation.

Economic and recreational use

The waterway is a crucial artery for the domestic shipping of bulk commodities, including petroleum, chemical products, and construction materials, serving industries from the Port of New York and New Jersey to the Port of Corpus Christi. It also supports substantial commercial fishing and shipbuilding activities in locations like Pascagoula, Mississippi. For recreational boaters, it forms part of the storied Great Loop circumnavigation of the eastern United States, with major marinas and tourist destinations found in cities like Charleston, South Carolina, Annapolis, Maryland, and Key West.

Environmental impact

The construction and maintenance of the waterway have significantly altered coastal ecosystems. Dredging and channelization have disrupted natural sediment flows, contributing to erosion and wetland loss in sensitive areas like the Louisiana coast. The introduction of artificial inlets can alter salinity gradients in estuaries, affecting species like the Eastern oyster and sea grass beds. Environmental regulations, including the Clean Water Act and oversight by the United States Environmental Protection Agency, now require careful assessment of maintenance projects to mitigate impacts on habitats within the National Estuarine Research Reserve system and other protected areas.

Category:Canals in the United States Category:Transportation in the United States Category:United States Army Corps of Engineers