In the state of South Carolina, canal building started soon after the U.S. Revolution, however these were primarily well inland and not along the coastline. The Old Santee Canal connected the Cooper River just east of Moncks Corner with the Santee River twenty-two (22) miles north in the Charleston District (now Berkeley County). After the U.S. Civil War and most of Reconstruction was behind them, South Carolinians launched several new canal projects, including the rework of some existing canals plus the dredging of several new ones.
In 1912, the U.S. Army Corps of Engineers submitted a report to Congress on their survey of the long-considered Intracoastal Waterway from Boston, MA to Beaufort, NC. They recommended that the existing Albemarle & Chesapeake Canal be redredged to a depth of twelve (12) feet and that it be considered as the primary route for the waterway. Congress approved, and on April 30, 1913 the U.S. government purchased the Albemarle & Chesapeake Canal for $500,000 and construction began soon thereafter.
In 1913, the U.S. Army Corps of Engineers submitted its next report to Congress on the next phase of the Intracoastal Waterway - from Beaufort, North Carolina to Key West, Florida. Those making and presenting the survey recommended a ten-foot deep waterway for the entire distance of 925 miles, to be completed in six (6) years at an estimated cost of $31 million. Brigadier General William H. Bixby, the Chief of Engineers, concurred with the need, but saw no urgency for one ten feet deep or, in view of the sparse population of Florida at that time, for construction as far south as Key West.
He recommended a seven-foot canal as far south as the St. John's River, which was estimated to cost about $14.4 million. The Board of Engineers for Rivers and Harbors declined to endorse either recommendation. Congress took no action either.
Ultimately, this "phase" was developed, not as a single project, but in several sections improved by stages in response to expectations of commercial benefit. The entire Intracoastal Waterway remained a string of variously-named projects until 1947, when all but the last two of the southern reaches were collectively designated the "Atlantic Intracoastal Waterway between Norfolk, VA and St. John's River, FL."
Begun in 1930, the last phase of the Intracoastal Waterway of the mid-Atlantic passed down the Cape Fear River to Southport, near the river's mouth, then followed the Elizabeth River (Brunswick County) to its headwaters, cut 2.6 miles through high ground to the head of Davis Creek, descended this creek, and continued through coastal sounds and marshes to the Little River in South Carolina. The waterway ascended the Little River to its headwaters, cut nearly twenty-two (22) miles through land to the head of Socastee Creek, thence followed the creek and the Waccamaw River to Winyah Bay - a complete distance of 94.5 miles, ending at Georgetown, South Carolina.
This last segment in North Carolina, which extended well into South Carolina, provided for a waterway eight (8) feet deep and seventy-five (75) feet wide, and was completed in 1936. The next year, Congress approved a channel twelve (12) feet deep with a bottom width of not less than ninety (90) feet.
Before construction began on this segment in 1930, inland navigation between the Cape Fear River and Winyah Bay had been impossible. The depth of water in the Elizabeth River, the Little River, and in Socastee Creek diminished to nothing at their heads, and in other places shallow channels and marshes could not be traveled by rowboats on low water. Where the land cuts were made, elevations reached thirty (30) to thirty-two (32) feet. The only earlier navigation work along the proposed route had been the dredging of the Waccamaw River, authorized in 1880, to clear shoals as far upriver from its mouth at Winyah Bay to the town of Conway, in Horry County.
Leaving Winyah Bay eight (8) miles below the port of Georgetown, the Intracoastal Waterway passed through the Estherville Minim Creek Canal to the North Santee River, cut through Four Mile Creek to the South Santee River, and then threaded through low coastal islands to Charleston Harbor - for a total distance of 63.5 miles. For much of this course, it followed a natural waterway, originally eighty-six (86) miles long, that had allowed the passage of small vessels, but was in many places obstructed by crooked channels and shallow reaches where low water depths did not exceed one foot. More dangerous were stretches across Bulls Bay and near Cape Romain that were exposed to the Atlantic.
Improvements to the existing waterways were begun in 1900 with the construction of the Estherville Minim Creek Canal for the passage of Santee River steamers to Winyah Bay. A second effort was initiated in 1902 to enlarge the channel from Charleston to McClellanville, about two-thirds of the distance to Winyah Bay, to four (4) feet deep and sixty (60) feet wide - and it was rerouted to eliminate the open stretch across Bulls Bay. Nothing more was done in this area until 1919, when the U.S. Army Corps of Engineers extended these channel dimensions through to the Estherville Minim Creek Canal along a new course that avoided the exposed run near Cape Romain.
In 1925, Congress authorized the cut across the Santee Delta at Four Mile Creek, which shortened the waterway by ten (10) miles. In 1932, the Corps recommended constructing a channel ten (10) feet deep and ninety (90) feet wide, generally following the existing route. This project was included in the Public Works Program launched in 1933 to stimulate the state's economy and was completed in 1936. In 1937, legislation established uniform dimensions for the Intracoastal Waterway from the Cape Fear River to Savannah, which increased the depth to twelve (12) feet - and this was completed by 1940.
Leaving Charleston Harbor south, the Intracoastal Waterway passed from the Ashley River through the Wappoo Cut and continued along a sinuous string of tidal streams and land cuts 66.5 miles to the Beaufort River at Beaufort, South Carolina. Better than the segment to the north of Charleston, the existing inland water course from Charleston to Beaufort had a minimum depth of six (6) feet, interrupted at only four locations, and, except for a six (6) mile passage across the St. Helena Sound, was well protected from the sea.
Earlier work on this segment of the waterway tackled its most problematic stretches. The first undertaking was at Wappoo Cut, a crooked and shallow creek that joined the Ashley and Steno rivers. By dredging and by a cutoff bypassing some of the worst bends, a project authorized in 1881 created a channel through the cut six (6) feet deep and sixty (60) feet wide. At the other end of this segment, a project adopted in 1890 improved Brickyard Creek. A continuation of the Beaufort River, Brickyard Creek had a fairly good seven (7) foot channel except near its juncture with the Coosaw River, where the channel practically disappeared among shoals. Work completed in 1905 provided the creek with a constant seven (7) foot depth and "convenient width." A third improvement, made in 1905-1906, was the construction of Fenwicks Island Cut in the central portion of this segment. It replaced a narrow, tortuous, and shallow passage through Mosquito Creek - the cut, seven (7) feet deep and ninety (90) feet wide, connected the South Edisto River with the Ashepoo River.
In 1925, Congress consolidated these earlier improvements into a single project for the Intracoastal Waterway from Charleston to Beaufort to be seven (7) feet deep and not less than seventy-five (75) feet wide. Completed in 1929, the Corps' work consisted mainly of widening and deepening the channel in the Steno River, where in palces the low water depth had dropped to four (4) feet; constructing another cutoff at Wappoo Cut to eliminate a sharp curve; and, cutting a new channel between the Dawho and South Edisto Rivers to avoid more sharp bends and shorten the waterway by nine (9) miles.
In 1931, a U.S. Army Corps of Engineers report recommended eliminating the exposed passage across the St. Helena Sound by excavating two short cuts through the marshes between the Ashepoo and Coosaw rivers. This work, authorized under the Emergency Relief Appropriation Act of 1935 and included in a rivers and harbors Act later in the same year, was completed in 1936. In 1937, the Corps resumed construction on the entire waterway between Charleson and Beaufort to bring the channel to the 12-foot-deep, 90-foot-wide dimensions authorized that year for the Intracoastal Waterway from the Cape Fear River to Savannah - and this effort was completed in 1940.
Between Beaufort, South Carolina and the St. John's River in Florida, the Intracoastal Waterway consisted mostly of natural water courses through sounds and tidal marshes. Several artificial cuts helped shorten the route and avoid exposed areas. Two hundred and seven (207) miles long, this segment offered intermediate connections with Port Royal in South Carolina, Savannah, Darien, and Brunswick in Georgia, and Fernandina in Florida.
Even before improvements of the waterway, light-draft boats had carried considerable commerce between Beaufort and Savannah. Between Savannah and Fernandina, where the controlling depth of water was only three (3) feet, traffic had been lighter. Between Fernandina and the St. John's River, which the waterway entered a few miles from its mouth, nature had negleced to provide a suitable channel, but private interests had opened a shallow passage early in the nineteenth century by making cuts to connect streams paralleling the coastline.
Until 1917, the U.S. Army Corps of Engineers improved these portions of this segment under separate authorizations. Between 1828 and 1839, the Corps dredged shoals at several locations, chiefly in the cuts between Fernandina and the St. John's River. Nothing else was done until 1874, when Congress called for dredging between the St. John's River and Nassau Inlet in order to provide a better outlet for the commerce of the St. John's River than across the treacherous bar blocking the river's mouth. Six (6) years later, however, upon the adoption of plans for improving the entrance of the St. John's River, the project was abandoned. The channel soon shoaled to 2.5 feet and remained in this condition until 1913. That year, Congress authorized a new project, completed in 1915, to open a waterway between Fernandina and the St. John's River seven (7) feet deep and one hundred (100) feet wide.
Between Savannah and Fernandina, the first navigation improvements deepened passages at Romerly Marsh in 1892 and at Jekyl Creek in 1888. In 1892, work began on a constant seven (7) foot channel. A separate project of 1905 improved Skidaway Narrows, a twisting and shallow passage near Savannah that was much used in preference to the normal route because it was safer in bad weather and shorter in length. In 1912, Congress incorporated the Narrows and four (4) other water courses used as alternate routes, or auxiliary channels, into the "Savanna to Fernandino Waterway."
Work between Beaufort and Savannah began in 1896, with a project to deepen the natural waterway between the two towns to seven (7) feet throughout its course. Because current plans for improving the Savannah Harbor included closing old entrances, a new entrance was to be cut into th Savannah River near its mouth. Three (3) years later, however, the waterway was re-routed to move the entrace upriver to a less exposed location. In 1912, a similar change of route was made where the waterway entered the Beaufort River to bring it into the shelter of Parris Island. Twenty-five (25) years later, this passage was abandoned in favor of the deeper water of the Port Royal Sound.
The Rivers and Harbors Act of 1917 consolidated the projects of this segment into the "Waterway between Beaufort, SC and St. John's River, FL." All work under this new authorization, which included several cuts that considerably shortened the length of the waterway, was completed in 1932. In 1937, the waterway as far south as Savannah came under the provision of that year for establishing a 12-foot-deep, 90-foot-wide channel from the Cape Fear River. The next year, upon the request of commercial carriers, Congress authorized the extension of the 12-foot channel to the St. John's River, which was completed in 1941. Between 1919 and 1945, Congress also provided for the construction of an anchorage basin in Thunderbolt, Georgia, and for the incorporation into the project of five more ancillary channels connecting with intermediate points or offering more protected passages.