The following text from the 1832 American State Papers proposes the construction of works known in the present day as the Tenn-Tom Waterway, the Gulf Intracoastal Waterway from Bon Secour to Pensacola, Fort Morgan and Fort Gaines (there's even a forshadowing of THE ESTUARIUM!)  :
Mobile Bay lies 40 miles west of Pensacola Bay. It receives the Alabama and Tombeckbee Rivers, the navigable waters of which flow through the State of Alabama, and will, by improvements in their head branches, connect the southern district of Tennessee, and the western of Georgia, with the Gulf of Mexico. The entrance of this bay is between the eastern point of Dauphin island and Mobile Point. The distance from one point to the other is 3 and one quarter miles. A bank projecting 5 miles to the southward of Mobile Point, obstructs the entrance of the bay; but, however, affords through it various channels, the main of which offers on the bar, 15 and a half feet at the lowest tide, and comes from the south around Mobile Point. The interior of the bay has water enough for any vessel which can pass over the bar; but, on account of a shoal formed opposite to the mouth of Dog River, 11 miles south of Mobile city, vessels drawing more than eight or nine feet cannot, at low tide, ascend the bay further up, and reach the mouth of Mobile River.  In following close to the out shore of Dauphin island, and leaving to the east Big Pelican island, vessels drawing 7 feet can, at low tide, enter the bay- in coming from the westward and steering close round a spit of sand, which projects out one and one quarter miles from the eastern end of Dauphin island; besides, there is a good anchorage between Big Pelican island and Dauphin island, and close to the latter, for vessels drawing 12 feet. This anchorage can be entered either from the westward, in steering close to Dauphin Island, or from the main channel, leaving it two miles southwest of Mobile Point.  During a prevalence of northerly wind, vessels from the sea being prevented from entering the bay, this anchorage affords them a good shelter to wait for a favorable wind. The main channel has a width, of 1600 yards for a least depth of 16 feet opposite Mobile Point. Between this channel and Dauphin Island, vessels drawing 7 feet can, at high tide, pass almost in every direction over the banks which lie at the entrance of the bay. The mean rise of tide is two and a half feet. A good anchorage is found at Navy Cove, north of Mobile Point, and vessels drawing 9 feet can reach, within four miles, the mouth of Bon Secours River, which enters into a bay of the same name. It is through this river, as it will be said hereafter, that the bay of Mobile might be connected by water with the bay of Pensacola. The defence of the entrance of Mobile Bay will rest on the occupation, by permanent works, of Mobile Point, and of the eastern end of Dauphin Island. Whilst the former point will defend the main channel, the other will overlook the western pass, as also the anchorage between Dauphin Island and Big Pelican Island, and both together will, within their respective range, control, as much as practicable, the shoal, over which small vessels might enter the bay. The work at Dauphin Island will, besides, ensure the possession of the island, and prevent an enemy from making on it, in time of war, a permanent establishment. From such an establishment, a naval adversary might cut off the coasting navigation between Mobile Bay and New Orleans, through Lake Pontchartrain; and, moreover, blockade the bay and interrupt the extensive trade destined to be carried through this estuary of the Alabama and Tombeckbee rivers. In fine, the work at Dauphin Island will protect the anchorage of steam batteries, which might become necessary in time of war, to scour the coast, to keep free the navigation of the sound leading from Lake Borgne and Lake Pontchartrain to Mobile Bay; and, also, to prevent the blockade of the mouth of the Mississippi, as well as of the entrances into Lake Pontchartrain.
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