The present invention relates to a retractable floodwall unit that comprises a foundation unit having a plurality of guide tracks along side walls of the foundation unit, a floodwall panel stowed in the foundation unit; and a power system for raising and lowering the floodwall panel. The foundation unit includes a first housing unit enclosing an actuator of the power system, and the floodwall panel includes a plurality of guides that mate with the guide tracks of the foundation unit.

An undershot gate system controls flow of liquid through an open channel or pipe. The system includes a gate leaf adapted to be raised and lowered by a control to allow flow of liquid along the open channel or pipe. The gate leaf has a flow diverter at an end of the gate leaf to guide liquid under the gate leaf and through an opening when the gate leaf is in an open position.

An undershot gate system controls flow of liquid through an open channel or pipe. The system includes a gate leaf adapted to be raised and lowered by a control to allow flow of liquid along the open channel or pipe. The gate leaf has a flow diverter at an end of the gate leaf to guide liquid under the gate leaf and through an opening when the gate leaf is in an open position.

A mechanical closure device comprises an enclosure having four sides, a top and bottom and defining a discharge opening at the bottom. A floodgate assembly is interiorly removably mounted to the enclosure and comprises a pair of doors pivoted on a hinge assembly between an opened position and closed position. In the closed position, the doors seal against the flange to prevent passage of water through the discharge opening. A discharge drain assembly is preferably disposed on one door and has an opened and a closed position. An appendage is provided to facilitate opening and of the door. Upon removal, the floodgate assembly is stably positionable on a multipositionable service rack. A multipurpose tool is employed unlatching the floodgate doors and slidably removing the floodgate assembly.

A mechanical closure device comprises an enclosure having four sides, a top and bottom and defining a discharge opening at the bottom. A floodgate assembly is interiorly removably mounted to the enclosure and comprises a pair of doors pivoted on a hinge assembly between an opened position and closed position. In the closed position, the doors seal against the flange to prevent passage of water through the discharge opening. A discharge drain assembly is preferably disposed on one door and has an opened and a closed position. An appendage is provided to facilitate opening and of the door. Upon removal, the floodgate assembly is stably positionable on a multipositionable service rack. A multipurpose tool is employed unlatching the floodgate doors and slidably removing the floodgate assembly.

A mechanical closure device comprises an enclosure having four sides, a top and bottom and defining a discharge opening at the bottom. A floodgate assembly is interiorly removably mounted to the enclosure and comprises a pair of doors pivoted on a hinge assembly between an opened position and closed position. In the closed position, the doors seal against the flange to prevent passage of water through the discharge opening. A discharge drain assembly is preferably disposed on one door and has an opened and a closed position. An appendage is provided to facilitate opening and of the door. Upon removal, the floodgate assembly is stably positionable on a multipositionable service rack. A multipurpose tool is employed unlatching the floodgate doors and slidably removing the floodgate assembly.

A mechanical closure device comprises an enclosure having four sides, a top and bottom and defining a discharge opening at the bottom. A floodgate assembly is interiorly removably mounted to the enclosure and comprises a pair of doors pivoted on a hinge assembly between an opened position and closed position. In the closed position, the doors seal against the flange to prevent passage of water through the discharge opening. A discharge drain assembly is preferably disposed on one door and has an opened and a closed position. An appendage is provided to facilitate opening and of the door. Upon removal, the floodgate assembly is stably positionable on a multipositionable service rack. A multipurpose tool is employed unlatching the floodgate doors and slidably removing the floodgate assembly.

A tank arrangement, duplicate cross-sectional restrictions, side roller block, openable reaction roller, openable bottom seal, reaction axle, openable side seal, gate slot inserting steps and a stress reduction cross-sectional restriction are presented to implement an emerging movement type opening/closing gate equipped with advantageous torsion structure. The arrangement enables a gate body to be operated in submerged-body state, the cross-sectional restrictions can correspond to both high tide pressure and tide flow pressure which are different in qualities, the side roller block, the openable reaction roller and the openable bottom seal resolve spatial interference problems in gate operation, compact reaction axles which endure big load enables cross-sectional restriction points at a narrow gap in a storage space, the openable side seal and the gate slot inserting steps prevent side seal rubber from damage and the stress reduction cross-sectional restriction can cut high tide pressure torsion moment by more than 50%.

A tank arrangement, duplicate cross-sectional restrictions, side roller block, openable reaction roller, openable bottom seal, reaction axle, openable side seal, gate slot inserting steps and a stress reduction cross-sectional restriction are presented to implement an emerging movement type opening/closing gate equipped with advantageous torsion structure. The arrangement enables a gate body to be operated in submerged-body state, the cross-sectional restrictions can correspond to both high tide pressure and tide flow pressure which are different in qualities, the side roller block, the openable reaction roller and the openable bottom seal resolve spatial interference problems in gate operation, compact reaction axles which endure big load enables cross-sectional restriction points at a narrow gap in a storage space, the openable side seal and the gate slot inserting steps prevent side seal rubber from damage and the stress reduction cross-sectional restriction can cut high tide pressure torsion moment by more than 50%.

The present invention relates to a retractable floodwall system comprising a floodwall panel installed in a housing unit. The floodwall panel is connected with a counter-balance weight. The floodwall panel is capable of being raised from the housing unit and being lowered into the housing unit. The present invention also relates to a method of flood prevention comprising providing a floodwall panel in a housing unit; connecting the floodwall panel with a counter-balance weight; raising the floodwall panel from the housing unit for flood prevention; and lowering the floodwall panel into the housing unit.