Although many people believe what we call the Intracoastal Waterway is a natural body of water, it is actually a man-made feature, created by connecting and dredging various lakes, tidal streams, bays and inlets that were located just inside the coastline. Parts of the Intracoastal were established in the early 19th century, but Florida, sparsely populated at that time, could not provide an economic justification for building a canal within its eastern shoreline.

The development of a continuous waterway along Florida's east coast was left to private enterprise. In 1883 the Florida Coast Line Canal & Transportation Company began construction from the St. Johns River to Biscayne Bay that continued until 1912, when the last section of the Florida East Coast Canal was completed. By charter requirements the company was to provide a channel 5 feet deep and 50 feet wide, but whether because of inadequate toll receipts or greater interest in profiting from the sale of lands granted by the state to subsidize construction, it failed to maintain these dimensions.

In 1929 a Florida Inland Navigation District created by the state purchased the canal properties and conveyed them to the United States. Financed in large part by Public Works funds, the construction of the waterway was completed in 1935.

(excerpted from History of the Waterways of the Atlantic Coast of the United States)