The DENIOS Automatic Doorway Flood Barrier System keeps floodwaters out of facilities by providing a flood “wall” at doorways. It installs easily in existing doorways and stores horizontally in the floor, permitting normal vehicular and personnel traffic, until a flood occurs. With the first flow of water the Barrier automatically closes. No additional ramps or berms are needed. The barrier fits door heights of 12, 18, and 24 inches and widths from 3 to 12 feet. Other features include solid welded stainless steel construction, self-contained one piece system design, fully automatic operation and no external power source or factory compressed air required.