The hold level is the lowest level on the ship, just above the keel. This is commonly known as the "bilge." This level is essentially divided into three sections, forward storage areas, engine and motor rooms and aft storage areas.
The forward section starts at the bow with the peak tank. Next aft is the underwater sound room and rodmeter compartment. The next space is the hedgehog storage magazine. Further aft is small arms storage magazine and ordnance stores with hatch to the second platform. The next area is Supply Division stores. This is followed by diesel oil tanks. There is no access further aft through the engine and motor sections.
The middle section consists of the forward engine room, forward motor room, aft engine room and aft motor room. These are all accessed independently from hatches in the main deck passageway on the starboard side of the galley and muffler rooms. There are emergency exit hatches on the main deck on the port side. There is no access between the engine and motor rooms at this level.
The aft section following the engine and motor rooms start with a series of diesel oil tanks and fresh water tanks, ammunition magazines and store rooms. The last area is a depth charge magazine on the centerline above the keel.