The Portable Nuclear Radioactive Fallout Protection Shelter & Preservation of Potable Water Storage System is comprised of self-supporting interlocking stackable radiation shielding watertight jugs having the dual purpose of being used to rapidly assemble fallout shelters and to store drinking water. The jugs are made of rigid neoprene, plastics, or similar substances that when filled with water and properly assembled omits radioactive gamma and X-rays. Wooden or metal support beams may be required when ceiling supports are necessary. The jugs may be filled using a common garden hose and be emptied by pouring water out of the water spouts that are also an integral part of the self supporting interlocking mechanisms and be drained by pouring water from the spouts or using a siphon hose or water pump. The system implements the construction of walls, modules, and complete protective shelters inside or outside of existing buildings.