With the fall of Savannah, attention in the Department of the South turned to Charleston. Among some Federal leaders there was concern the Confederates might feel the situation desperate enough to try a “go for broke” attack.
Throughout late November and early December 1864, there was some concern of a Confederate boat attack on Morris Island, along the lines of that proposed by Brigadier-General Roswell Ripley. But when Brigadier-General Alexander Schimmelfennig returned from leave, he discounted such rumors. Reporting to Major-General John Foster, he indicated all was routine around Charleston. However, Schimmelfennig did direct repairs to defensive arrangements which had been neglected. In particular on December 26, he directed “dry brush to be piled up in front of the forts and batteries on [Morris Island] where the ground admits, at a distance of from 200 to 300 yards.…” This brush, placed out past musket distance from the fortifications, would be set on fire in the event of a Confederate attack. The intent was, with the brush so far out in front of the works, for it to illuminate the ground directly in front of the works and leave the attackers silhouetted and easy targets.
At the same time, the Navy was concerned the Charleston Squadron, chiefly the ironclad rams CSS Charleston, CSS Palmetto State, CSS Columbia and CSS Chicora, would sortie out of Charleston in an attempt to break the blockade. After all, the CSS Savannah was preparing to make just such a breakout when Savannah fell. Shortly after Christmas, Captain Gustavus H. Scott, senior officer on the blockade outside Charleston, suggested to Rear-Admiral John Dahlgren that the Confederates were preparing for a breakout. In response, Dahlgren took a break from matters at Hilton Head to visit the old front at Charleston.
Dahlgren felt secure the monitors on blockade duty at that time were sufficient to deal with the threat. But he did remind the Navy Department that several of the monitors had been on station for quite some time. That in mind, along with the growing possibility of an engagement, Dahlgren asked for replacements, “otherwise there is no small risk that one or two may become unserviceable.”
Coordinating with Schimmelfennig on December 29, Dahlgren downplayed any concerns:
Though I felt no apprehension as to the ability of the force here to maintain control of the anchorage, and even capture the rebel ironclads if they ventured out, yet, as I might be drawn in some other direction at the time, it seemed due to the perfect security of General Sherman’s base that no means should be omitted. I have, therefore, reinforced the division, there are now seven monitors here, which I think places the question beyond doubt.
Seeking to coordinate for the contingency, Dahlgren related some of his thinking to the commander ashore:
In case the ironclads venture out, my plan will be to draw them as low down this anchorage as they will come, so as to make sure of the capture of the whole by making retreat impossible.
In such an event, will you please cause some of your heavy guns to be turned seaward, and scour the water with grape so as to clear out the torpedo boats which might be troublesome when engaged with the rams.
Having seen the defenses of Savannah up close, and concerned the Confederates might further improve the defenses of Charleston, Dahlgren added:
The rebels will, no doubt, endeavor to increase the obstructions in the harbor, and some grape or mortar shells at night from your guns near Johnson and the Middle Ground would stop them. The naval battery will assist in this if you think proper.
After seeing the works about Savannah and the obstructions in the rivers (Savannah, Tybee, Vernon, and the Ogeechee), I am satisfied it was impregnable to any force in any direction save where it was assailed by General Sherman.
To Captain Scott, Dahlgren provided detailed contingency plans on December 31. Scott was told to ensure the monitors and blockaders act in consort in the case of attack, and not as single units. Particularly, Dahlgren wanted no monitors “separated from the main body before they can receive assistance.” Altering the normal arrangements, Dahlgren specified that:
At night, if the weather is suitable, four monitors are to be pushed in advance, the other three in reserve at a convenient distance, and two of them may be allowed to draw fire under one boiler at a time to clean and repair, but even these vessels should be made available if an attack is made.
To counter torpedo boats and laying additional obstructions, Dahlgren called for alert picket boats (though without mention of a picket boat captured earlier in the month). In the event of a torpedo boat attack, the monitors and the land batteries were to “scour the water with grape at intervals.”
In the event the ironclads moved out of the harbor, Dahlgren’s orders to Scott reflected the intentions voiced to Schimmelfennig:
It will be an object to draw them as much as possible under the fire of our land batteries, and to avoid exposing the monitors to their batteries…. The lower down the channel they can be drawn into action the less probable it will be that any escape. If high up and beaten, they will find protection under their own batteries on Sullivan’s Island, South Carolina.
A sound plan. But not one that would see a need. The Confederate squadron in Charleston was bottled up for similar reasons the Savannah Squadron had been doomed weeks before.
(Citations from OR, Series I, Volume 44, Serial 92, page 819; ORN Series I, Volume 16, pages 151-4.)