Abstract: A surge flushing device for wastewater systems and the like includes a wastewater channel having an arc-shaped wall portion, as well as a flushing blade element having a marginal portion thereof shaped to selectively mate with the wall portion of the channel, and mounted for shifting in a direction generally perpendicular to the direction of flow in the channel between a lowered, closed position, and a raised, open position. A gasket has a base portion supported on the marginal portion of the blade element and an elastically deformable lip portion which protrudes radially outwardly therefrom, and abuttingly engages the wall portion of the channel when the blade element is in the lowered, closed position, in an elastically deformable curved shape which opens outwardly in a direction opposite to the direction of flow in the channel to selectively form a secure seal therebetween.

Abstract: The device for controlling fluid flow from a rain retention chamber or the like includes an inlet communicating with the chamber, an outlet permitting fluid to flow out of the device, and a shutter disposed between the inlet and the outlet, and supported in the device for linear shifting between a raised position and lowered position. A control element is rotatably mounted in a device for rotation about a central axis and includes a curved controller surface which is non-concentric with the central axis of the central element, such that rotation of the control element varies the radial distance between the central axis and the controller surface. A coupler member operably connects the shutter with the controller surface, such that rotation of the control element shifts the shutter between the raised and lowered positions to achieve a predetermined flow rate of fluid from the chamber.