A flap gate includes a door body and a flap ancillary part. When the door body is in its down position, a movable end portion of the door body is located forward of a supported end portion. The door body changes its position between the down position and a maximum up position. The flap ancillary part applies tilt-up moment to the door body only when the door body is located in a position between the down position and a first position. The flap ancillary part also applies tilt-down moment to the door body only when the door body is located in a position between the maximum up position and a second position.

The invention concerns a flood protection for protecting a back area against rising water level from a front area, the flood protection operating between a bottom and a water surface, including at least one barrier element with a longitudinal direction and a height direction, the longitudinal direction during operation extending substantially transversely of an area, e.g. a stream, a fjord, a river or an estuary, and the height direction during operation extending from the bottom of an area, e.g. a stream, a fjord, a river or an estuary, and up, where the at least one barrier element during operation interacts with a base arranged at the bottom of the actual area. The invention also concerns a method for operating such a flood protection. The new feature of the flood protection according to the invention is that it includes a movable and buoyancy balanced barrier element that includes an adjustable ballast system for regulating the buoyancy balance, the base of the flood protection including a bottom rail system, and the barrier elements including contact means arranged for contact with the bottom rail system.

A method for protecting a building against flooding by use of a membrane connected along a first side edge to a float, and comprises the steps of arranging the membrane in a packed configuration at a first distance from the building, and fixing the membrane to the ground at a start location along a second side edge, allowing water to unpack the membrane and move the float toward the building to arrange a first portion of the membrane with a lower surface against ground in an area between the start location and the building, allowing water to raise the float a second distance along an outer surface of the building while further unpacking the membrane to arrange a second portion of the membrane with the lower surface against the building. The first portion forms a retention portion which is retained on the ground by water on an opposite upper surface.

The present invention relates to a self-raising wave barrier for providing an alleviation of a load due to wave action from a body of water on the side of the wave barrier remote from the body of water. The barrier includes a series of barrier assemblies providing alleviation of the load due to the wave action. Each barrier assembly includes a holder for a wave barrier element which is anchored to a bottom of the body of water or a surface adjacent to the body of water, a wave barrier element arrangeable movably over a path of movement in the holder between a lower rest state and a higher active state, and holding means for holding and/or stopping the wave barrier element in the higher active state.

A system for flood control that includes: a water sensor; a control panel, where the water sensor is connected to the control panel; and a convertible sea wall, where the convertible sea wall is adapted to toggle between an extended position and a retracted position. The system for flood control may further include a steel base structure, wherein the steel base structure houses the convertible sea wall when the convertible sea wall is in a retracted position. The steel base structure further includes hydraulic lifts within the steel base structure that lift and extend the convertible sea wall into the extended position and allows for the retraction of the sea wall to the retracted position.

A method for protecting a building against flooding by use of a membrane connected along a first side edge to a float, and comprises the steps of arranging the membrane in a packed configuration at a first distance from the building, and fixing the membrane to the ground at a start location along a second side edge, allowing water to unpack the membrane and move the float toward the building to arrange a first portion of the membrane with a lower surface against ground in an area between the start location and the building, allowing water to raise the float a second distance along an outer surface of the building while further unpacking the membrane to arrange a second portion of the membrane with the lower surface against the building. The first portion forms a retention portion which is retained on the ground by water on an opposite upper surface.

A wall resident in a subterranean chamber and not obscuring a horizontal ground level view is situated between buoyant panels flanking the chamber and is configured to be passively rotationally raised out of the chamber to an upright position by one or both of the flanking panels when the panels rotationally buoy upward to form a barrier against water invading the position that the wall, chamber and panels occupy. When flood waters recede, the wall passively lowers so the horizontal ground level view is again not obscured. Provision is made for cleaning flood laden debris from the subterranean chamber to allow the wall to be operated repeatedly after recurring floods.

A system for flood control that includes: a water sensor; a control panel, where the water sensor is connected to the control panel; and a convertible sea wall, where the convertible sea wall is adapted to toggle between an extended position and a retracted position. The system for flood control may further include a steel base structure, wherein the steel base structure houses the convertible sea wall when the convertible sea wall is in a retracted position. The steel base structure further includes hydraulic lifts within the steel base structure that lift and extend the convertible sea wall into the extended position and allows for the retraction of the sea wall to the retracted position.

A flap gate includes a door body and a flap ancillary part. When the door body is in its down position, a movable end portion of the door body is located forward of a supported end portion. The door body changes its position between the down position and a maximum up position. The flap ancillary part applies tilt-up moment to the door body only when the door body is located in a position between the down position and a first position. The flap ancillary part also applies tilt-down moment to the door body only when the door body is located in a position between the maximum up position and a second position. This simplifies the structure of the flap gate that can speedily start to tilt up when water flows in and that can early start to tilt down when the water level has started to drop.

A weir comprising: a water impervious flexible membrane; a buoyancy member; and a tether, wherein, in use, the membrane comprises a lower edge portion and an upper edge portion, the lower edge portion is fixed with respect to a bed of a body of water, the membrane and the buoyancy member are attached to one another in the upper edge portion, and the tether comprises a first end portion, which is attached to the buoyancy member and/or to the membrane in the upper edge portion, and a second end portion that is attached to an anchorage.