Early in the war, torpedoes (mines) were placed in the Hog Island Channel to defend against Union ships that might slip past Fort Sumter and Fort Moultrie. The Hog Island Battery, also known as the Shem Creek Battery, was built on the southern tip of Hog Island in 1863. The small one-gun battery was constructed with an adjoining powder magazine. Hog Island was selected as the site to provide for additional inner harbor defense and to defend the village of Mount Pleasant.

The initial armament was an 8-inch Columbiad on a barbette carriage to allow for the widest field of fire. By May 1864, the armament was a 32-pound Navy gun.

The site of the Hog Island Battery is near the 18th green on the Patriots Point Golf Course. The battery is destroyed.