Abstract: An underdrain block for filtering water includes a top wall, a bottom wall, and two side walls connecting the top wall to the bottom wall to define an internal chamber. The bottom wall contains a plurality of orifices that allow liquid and solid materials to enter and exit the internal chamber. An underdrain filtering system can be formed by securing an underdrain lateral, which is formed from one or a plurality of underdrain blocks, to a filter floor. Also included is a method of preparing an underdrain lateral for providing even distribution of backwash water along the underdrain lateral and a method of validating even distribution of backwash water across an underdrain lateral.

Abstract: A filter media retainer has a plate having a first end wall, a second end wall, and a pair of longitudinal sidewalls connected to opposing sides of the first end wall and the second end wall. The plate has a top surface opposite a bottom surface. A plurality of hopper-shaped compartments are formed on the top surface and have a first sloped wall and a second sloped wall angled toward the first sloped wall in a direction from the top surface toward the bottom surface. The plate further has a top sidewall on the top surface of the plate separating adjacent hopper-shaped compartments from each other. The plate further has at least one first slot extending through at least one of the first sloped wall and the second sloped wall, and at least one second slot extending through the top sidewall.

Abstract: A filter media retainer has a plate having a first end wall, a second end wall, and a pair of longitudinal sidewalls connected to opposing sides of the first end wall and the second end wall. The plate has a top surface opposite a bottom surface. A plurality of hopper-shaped compartments are formed on the top surface and have a first sloped wall and a second sloped wall angled toward the first sloped wall in a direction from the top surface toward the bottom surface. The plate further has a top sidewall on the top surface of the plate separating adjacent hopper-shaped compartments from each other. The plate further has at least one first slot extending through at least one of the first sloped wall and the second sloped wall, and at least one second slot extending through the top sidewall.

Abstract: An underdrain block for filtering water includes a top wall, a bottom wall, and two side walls connecting the top wall to the bottom wall to define an internal chamber. The bottom wall contains a plurality of orifices that allow liquid and solid materials to enter and exit the internal chamber. An underdrain filtering system can be formed by securing an underdrain lateral, which is formed from one or a plurality of underdrain blocks, to a filter floor. Also included is a method of preparing an underdrain lateral for providing even distribution of backwash water along the underdrain lateral and a method of validating even distribution of backwash water across an underdrain lateral.

Abstract: A flush apparatus for a filter underdrain system can include a fluid connection member having a body with a first end and a second end, the first end adapted to connect to a fluid source; a top plate connected to the second end of the fluid connection member; and a bottom plate opposing the top plate and adapted to engage a top portion of an underdrain system, the bottom plate having orifices that distribute fluid to the underdrain system to transport materials through the underdrain system. A system for cleaning unwanted materials from a water or waste water treatment filter and a method of transporting unwanted materials through an underdrain system are also disclosed.