At a length of almost 3,000 miles, the Intracoastal Waterway (IWW) extends from Norfolk, Virginia to Key West, Florida. The Gulf Coast section extends from Carrabelle, Florida to Brownsville, Texas. This inland waterway was designed to provide a protected route for small-craft boaters to travel the United States within relatively sheltered waters. The Intracoastal Waterway traverses both natural and man-made channels to create a continuous, safe route for boaters.
The IWW was authorized in 1919 to provide a toll-free waterway for recreational boating use. The Intracoastal Waterway was originally intended to be a continuous inland channel from New York to Brownsville, Texas, with a proposed canal construction to cross the state of Florida. Due to environmental concerns, this plan was permanently blocked in 1971. Today, there are two sections to the IWW; the Atlantic IWW and the Gulf IWW. The Intracoastal Waterway is maintained by the U.S. Army Corps of Engineers.
The Intracoastal Waterway traverses sounds, bays and rivers using the best natural channels available. The U.S. East Coast has a natural, protected barrier-island design that allows boaters to travel within protected waters rather than traveling in the often-rough Atlantic Ocean. The East Coast portion of the Intracoastal Waterway is over 1,900 miles long. The Gulf Coast portion covers 1,050 miles.
Some portions of the IWW cross areas of heavy commercial traffic. The Intracoastal Waterway crosses Mobile Bay and the entrance to the Port of Mobile and the Mississippi Sound, as well as the entrance to the heavily trafficked Mississippi River.
The most prominent feature of the IWW lies in the maintained depth of this waterway. The Corps of Engineers maintains most depths of the waterway at 12 feet, although some sections are six to nine feet deep. The Corps of Engineers regularly dredges areas that develop shoals (areas of sand/silt deposition) to allow for vessel draft clearance. In most places, a boat with an eight-foot draft can travel safely through the IWW without running aground.
Dredged and natural channels are marked with aids to navigation to allow for safe travel along the IWW. It also contains some buoys and bridge clearances for taller boats, such as sailboats. In general, boats with a clearance above water of 62 feet can travel the IWW. Drawbridges and standard bridges exist along the entire waterway. This requires boaters to call ahead to bridge operators to allow time for the drawbridges to be opened.
Boaters traveling the Intracoastal Waterway not only have a protected route of travel but also the benefit of numerous privately owned marinas and facilities along the length of the waterway. These facilities cater to their boating customers, providing food, lodging and boat maintenance and repair services.
"Snow birds" escaping the cold weather in the northern states use the Intracoastal Waterway as a route of travel beginning in September each year. Thousands of boaters travel south along this waterway route that is nicknamed the "Boater's Route 66." Many of these boaters travel more than the recommended 50 miles per day. There's a mass exodus of boats heading north in May each year as temperatures warm in the northern states, making this one of most heavily traveled periods of time on the Intracoastal Waterway.