A dynamically deployable, low visibility pneumatic cofferdam for flood mitigation is disclosed. The cofferdam includes a first planar component, a second planar component, an inflatable hermetic airbag sandwiched therebetween, and connection members attached to the first planar component, a second planar component to form a cofferdam unit. The connection members are adjustable to apply and maintain a desired amount of pressure on the airbag to enable a watertight seal to be formed. The cofferdam units may be sized and designed to sealingly mate adjacent cofferdam units in a variety of configurations to form watertight seals. The cofferdam units may also be sized and designed to attach to seawalls, flood walls, sidewalks, or other infrastructure. When in a deployed state, the height of the cofferdam may be adjusted to a desired height to provide flood mitigation. When in an undeployed state, the cofferdam remains in a substantially flat and unobtrusive position.

A portable cofferdam system for isolating a working area from water such as a culvert. The portable cofferdam system generally includes a first sidewall and a second sidewall each having an interior side, an exterior side, an upper edge, a lower edge and a rear edge. A middle wall is connected to the sidewalls opposite of the rear edges of the sidewalls forming a substantially U-shaped structure. An opening formed between the rear edges of the first sidewall and the second sidewall to allow for positioning about or near the inlet of an object or area to be kept dry such as the inlet of a culvert.

A portable cofferdam system for isolating a working area from water such as a culvert. The portable cofferdam system generally includes a first sidewall and a second sidewall each having an interior side, an exterior side, an upper edge, a lower edge and a rear edge. A middle wall is connected to the sidewalls opposite of the rear edges of the sidewalls forming a substantially U-shaped structure. An opening formed between the rear edges of the first sidewall and the second sidewall to allow for positioning about or near the inlet of an object or area to be kept dry such as the inlet of a culvert.

The present disclosure relates to a cofferdam system securable to an underwater structure and across a body of water. The system includes a post support and anchoring assembly securable to the structure, a web support frame which extends upwardly from the post support and anchoring assembly in a spaced apart configuration from a surface defined by the underwater structure, as well as a substantially flexible impermeable web which is positioned across the body of water and which is adapted to cover the post support and anchoring assembly and at least a lower section of the web support frame outwardly therefrom. Such configuration of the system allows to provide a substantially dry enclosure from a dam upstream side between the substantially flexible impermeable web and the underwater structure when mounted thereto and once water is being removed from a dam downstream side. A method for installing the same is further described.

The present disclosure relates to a cofferdam system securable to an underwater structure and across a body of water. The system includes a post support and anchoring assembly securable to the structure, a web support frame which extends upwardly from the post support and anchoring assembly in a spaced apart configuration from a surface defined by the underwater structure, as well as a substantially flexible impermeable web which is positioned across the body of water and which is adapted to cover the post support and anchoring assembly and at least a lower section of the web support frame outwardly therefrom. Such configuration of the system allows to provide a substantially dry enclosure from a dam upstream side between the substantially flexible impermeable web and the underwater structure when mounted thereto and once water is being removed from a dam downstream side. A method for installing the same is further described.

A method for constructing a steel sheet pile cofferdam is provided, including: step S1, determining a construction area of the steel sheet pile cofferdam; step S2, piling steel casings, and welding guide frame brackets to the steel casings, the guide frame brackets are connected with a guide frame and limiting clamp plates; step S3, piling steel sheet piles by relying on the guide frame; step S4, pouring subsealing concrete at a bottom of the steel sheet pile cofferdam; step S5, arranging purlins and internal supports within the steel sheet pile cofferdam; step S6, perform a secondary subsealing at the bottom of the steel sheet pile cofferdam; step S7, pumping water within the steel sheet pile cofferdam through a pump and pouring to form a bearing platform on the subsealing concrete; step S8, removing the steel sheet pile cofferdam after the bearing platform is formed.

A method for constructing a steel sheet pile cofferdam is provided, including: step S1, determining a construction area of the steel sheet pile cofferdam; step S2, piling steel casings, and welding guide frame brackets to the steel casings, the guide frame brackets are connected with a guide frame and limiting clamp plates; step S3, piling steel sheet piles by relying on the guide frame; step S4, pouring subsealing concrete at a bottom of the steel sheet pile cofferdam; step S5, arranging purlins and internal supports within the steel sheet pile cofferdam; step S6, perform a secondary subsealing at the bottom of the steel sheet pile cofferdam; step S7, pumping water within the steel sheet pile cofferdam through a pump and pouring to form a bearing platform on the subsealing concrete; step S8, removing the steel sheet pile cofferdam after the bearing platform is formed.

A water containment apparatus includes a straight strut arrangement comprising a plurality of straight strut assemblies forming an alternating v-shape and inverted v-shape pattern; and a curved strut arrangement comprising a plurality of corner strut assemblies forming a desired curvature and connecting two straight strut arrangements to form a closed loop water containment system.

A water containment apparatus includes a straight strut arrangement comprising a plurality of straight strut assemblies forming an alternating v-shape and inverted v-shape pattern; and a curved strut arrangement comprising a plurality of corner strut assemblies forming a desired curvature and connecting two straight strut arrangements to form a closed loop water containment system.

A cofferdam is disclosed that includes an open frame structure having double walls defining a hollow space within each double wall, with each double wall having an open bottom end and a closed top end. Each of the double walls are configured to act as suction piles allowing liquid to be removed from the space within each double wall to thereby induce negative pressure when the cofferdam is installed in a sub-sea configuration. Each of the double walls may include a plurality of partitions respectively defining a plurality of suction piles, the suction piles fluidically coupled by a manifold that may allow liquid to be removed from the suction pile to thereby drive the cofferdam structure into the subsea surface due to the induced negative pressure. A further embodiment cofferdam structure includes an open frame structure and one or more suction piles attached to the open frame structure.