A temporary sediment retention assembly for removing sediment from storm water entering an inlet of a storm water drainage system can include a substantially rigid frame and a cover. The cover can include a cover material that includes one or more sections of filter materials. The sections of filter materials can be substantially integrally formed or can be connectable together, and form or define a covering or cap that is adaptable to fit over and substantially cover the frame of the temporary sediment retention assembly for retaining or filtering sediment and debris from water flowing through the temporary sediment retention assembly and into the storm water drainage system.

A temporary sediment retention assembly for removing sediment from storm water entering an inlet of a storm water drainage system can include a substantially rigid frame and a cover. The cover can include a cover material that includes one or more sections of filter materials. The sections of filter materials can be substantially integrally formed or can be connectable together, and form or define a covering or cap that is adaptable to fit over and substantially cover the frame of the temporary sediment retention assembly for retaining or filtering sediment and debris from water flowing through the temporary sediment retention assembly and into the storm water drainage system.

A conveyor-belt filtering device includes an endless filtering belt, which has at least one filtering element, a frame, a lower deflection apparatus and at least one upper deflection apparatus. The endless filtering belt has at least one collecting element, which is adapted for collecting foreign solids, in particular sand, stones, pebbles or the like, which are present in the liquid, in particular in an area of the lower deflection apparatus.

A stormwater treatment device includes a tank defining an internal volume and having an inlet and an outlet, a rotatable screen unit mounted within the tank, the rotatable screen unit being barrel-shaped to define a through path with an inlet end and an outlet end. The rotatable screen unit includes a screen structure with a plurality of screening openings for allowing passage of at least some water from the through path outwardly through the screen structure while inhibiting passage of trash items through the screen structure such that trash items move along the through path from the inlet end to the outlet end. The rotatable screen unit includes a plurality of external drive paddles that rotate with the screen structure and that interact with water that has been screened by passing outwardly through the screen structure interacts with the external drive paddles to cause rotation of the rotatable screen unit.

A stormwater treatment device includes a tank defining an internal volume and having an inlet and an outlet, a rotatable screen unit mounted within the tank, the rotatable screen unit being barrel-shaped to define a through path with an inlet end and an outlet end. The rotatable screen unit includes a screen structure with a plurality of screening openings for allowing passage of at least some water from the through path outwardly through the screen structure while inhibiting passage of trash items through the screen structure such that trash items move along the through path from the inlet end to the outlet end. The rotatable screen unit includes a plurality of external drive paddles that rotate with the screen structure and that interact with water that has been screened by passing outwardly through the screen structure interacts with the external drive paddles to cause rotation of the rotatable screen unit.

The present application provides a secondary drainage method for use at the time of flooding. A rainwater storage tank is provided, drainage pipes are installed between positions in which flooding of land or of property occurs and the rainwater storage tank, and inflow switching valves are installed in portions where water flows in from the drainage pipes to the rainwater storage tank. As a general rule, the flow of water into the rainwater storage tank is prevented by switching the inflow switching valves during the initial stages of a localized severe rain storm or of river flooding. After the wide-area flooding of land has receded, the inflow switching valves are opened, guiding the water in the locally remaining zones of flooded land or of flooded property into the rainwater storage tank, and allowing the localized flooding of land or of property to be eliminated at an early stage.

The present application provides a secondary drainage method for use at the time of flooding. A rainwater storage tank is provided, drainage pipes are installed between positions in which flooding of land or of property occurs and the rainwater storage tank, and inflow switching valves are installed in portions where water flows in from the drainage pipes to the rainwater storage tank. As a general rule, the flow of water into the rainwater storage tank is prevented by switching the inflow switching valves during the initial stages of a localized severe rain storm or of river flooding. After the wide-area flooding of land has receded, the inflow switching valves are opened, guiding the water in the locally remaining zones of flooded land or of flooded property into the rainwater storage tank, and allowing the localized flooding of land or of property to be eliminated at an early stage.

A channel for fluid flow comprising a first unit and a second unit connected to each other. The first unit comprises a first u-section having a first open top side, and a first grate extending across the first open top side and removably attached to the first u-section. The second unit comprises a second u-section having a second open top side, and a second grate extending across the second open top side and removably attached to the second u-section. The first grate defines a negative semicircular distal end having a first diameter and a first center point. The second grate defines a positive semicircular proximal end having a second diameter and a second center point. The first center point is coincident with the second center point and the first diameter and the second diameter are sized such that the positive semicircular proximal end fits within the negative semicircular distal end.

A channel for fluid flow comprising a first unit and a second unit connected to each other. The first unit comprises a first u-section having a first open top side, and a first grate extending across the first open top side and removably attached to the first u-section. The second unit comprises a second u-section having a second open top side, and a second grate extending across the second open top side and removably attached to the second u-section. The first grate defines a negative semicircular distal end having a first diameter and a first center point. The second grate defines a positive semicircular proximal end having a second diameter and a second center point. The first center point is coincident with the second center point and the first diameter and the second diameter are sized such that the positive semicircular proximal end fits within the negative semicircular distal end.

A connector pipe screen device configured for mounting on a water conduit includes an expandable ring mounting assembly, the expandable ring mounting assembly being configured to be engagable with and securable to the conduit near or at an axial end of the conduit at which a conduit opening is disposed, a back plate mounted on the expandable ring mounting assembly and a front cover mounted on the back plate. The front cover has a perforated portion defining a multiplicity of openings formed therein to allow water to pass through the perforated portion and to prevent debris carried by the water from passing through the perforated portion.