A self-activating flood barrier includes a chamber (1) having first and second side walls (3, 5), a dam member (9) adapted to self-deploy in the event of a flood to inhibit the passage of water to a region to be protected, and a low-friction device (77, 79) positioned between the dam member and at least one of the first and second side walls of the chamber when the dam member is deployed. The low-friction device prevents jamming between the dam member and the at least one side wall.

A mobile marine barrier (1) comprising a base (2) and a hood (8) located at a distal end thereof is described. The hood (6) comprises a funnel (15) and a distal surface (18) located therein which allows the hood (6) to morph its shape, size and strength so as to give adaptable coastal protection against naturally occurring events. This is achieved by incorporating a telescopic funnel such that the length of the hood (6) and thus the area of its open end can be altered so as to vary the quantity of water directed towards the distal surface (18). The hood (16) may also comprise a mobile face (17) that forms part of variable volume chamber (26) located within the hood (8) which can be filled and emptied with fluids.

A mobile marine barrier (1) comprising a base (2) and a hood (8) located at a distal end thereof is described. The hood (6) comprises a funnel (15) and a distal surface (18) located therein which allows the hood (6) to morph its shape, size and strength so as to give adaptable coastal protection against naturally occurring events. This is achieved by incorporating a telescopic funnel such that the length of the hood (6) and thus the area of its open end can be altered so as to vary the quantity of water directed towards the distal surface (18). The hood (16) may also comprise a mobile face (17) that forms part of variable volume chamber (26) located within the hood (8) which can be filled and emptied with fluids.

To provide a floating flap gate that requires an auxiliary force of a counterweight or the like, and in which bending does not occur in a forward end portion of a door body, even in cases in which an installation site has a wide span. A floating flap gate 1 having a forward end portion 2c of a door body 2 that is configured to rotate around a base end portion serving as a fulcrum at a time of a rising water, so as to float upwards, and provided with an upper beam 2d attached to the forward end portion 2c of the door body 2 and a door body suspension member 3 contained within the upper beam 2d, and having two ends each being connected to one end of a wire rope 4. A counterweight 5 is connected to the other end side of the wire rope 4 as a pulling device. Bolts 6b are used as adjusting members interposed between the upper beam 2d and the door suspension member 3, and are inserted into bolt holes 6a provided on an upper surface of the upper beam 2d, so as to exert an opposing force to the tension of the wire rope 4 resulting from the weight of the counterweight 5 acting on the door body suspension member 3, the opposing force being applied uniformly to the upper beam 2d during ordinary use.

A tidal barrage comprising: a plurality of spaced towers, a plurality of barriers for controlling water flow through the barrage between the towers, and one or more turbine devices, wherein the towers comprise at least first, second and third towers, wherein the first tower is located between the second and third towers and houses one or more of the turbines, wherein one or more first barriers are provided between the first and second towers, and one or more second barriers are provided between the first and third towers, wherein the barriers are configured so that when the one or more first barriers and the one or more second barriers are in a first configuration, a first flow path through the barrage is defined from a first side of the barrage to a second side of the barrage, and when the one or more first barriers and the one or more second barriers are in a second configuration, a second flow path through the barrage is defined from the second side of the barrage to the first side of the barrage, and water flowing through the first and second flow paths flows through the one or more turbines housed in the first tower in the same direction, wherein one or more of the barriers comprises a water impervious flexible membrane, a buoyancy member; and one or more tethers.

A tidal barrage comprising: a plurality of spaced towers, a plurality of barriers for controlling water flow through the barrage between the towers, and one or more turbine devices, wherein the towers comprise at least first, second and third towers, wherein the first tower is located between the second and third towers and houses one or more of the turbines, wherein one or more first barriers are provided between the first and second towers, and one or more second barriers are provided between the first and third towers, wherein the barriers are configured so that when the one or more first barriers and the one or more second barriers are in a first configuration, a first flow path through the barrage is defined from a first side of the barrage to a second side of the barrage, and when the one or more first barriers and the one or more second barriers are in a second configuration, a second flow path through the barrage is defined from the second side of the barrage to the first side of the barrage, and water flowing through the first and second flow paths flows through the one or more turbines housed in the first tower in the same direction, wherein one or more of the barriers comprises a water impervious flexible membrane, a buoyancy member; and one or more tethers.

A scupper door system includes a frame defining a passageway. A door is mounted within the frame at a pivot and is therein rotatable about the pivot within the passageway between a closed position, blocking the passageway, and an open position wherein the passageway is open to permit passage of water therethrough. A latch mechanism is configured to retain the door in the closed position and is triggerable in response to a preset water condition at one side of the passage to release the door from the closed position and allow the door to rotate to the open position.