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 filtration system having an underdrain block and an underdrain wall adaptor. The underdrain wall adaptor includes a vertical end and horizontal base. The vertical end extends from a top wall to a bottom wall of an underdrain block and mates with an end portion of an underdrain block to secure the underdrain wall adaptor to the underdrain block. The horizontal base extends from the vertical end. The invention also includes a method of installing an underdrain wall adaptor. The underdrain wall adaptor controls air and water passage between the flume and the underdrain.

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: An underdrain system for transferring forces and directing flow includes at least one underdrain block having a top wall, a bottom wall, and two side walls connecting the top wall to the bottom wall to define a block interior. An insert is disposed in the interior of the underdrain block. The insert includes force-transmitting buttresses spaced along an exterior of the insert that contacts the two side walls of the underdrain block and act to transfer downward forces acting on the top wall of the underdrain block and internal fluid forces acting on the insert to the side walls of the underdrain block. The force-transmitting buttresses can also direct hydraulic flow.

Abstract: A filtration system having an underdrain block and an underdrain wall adaptor. The underdrain wall adaptor includes a vertical end and horizontal base. The vertical end extends from a top wall to a bottom wall of an underdrain block and mates with an end portion of an underdrain block to secure the underdrain wall adaptor to the underdrain block. The horizontal base extends from the vertical end. The invention also includes a method of installing an underdrain wall adaptor. The underdrain wall adaptor controls air and water passage between the flume and the underdrain.

Abstract: An underdrain system for transferring forces and directing flow includes at least one underdrain block having a top wall, a bottom wall, and two side walls connecting the top wall to the bottom wall to define a block interior. An insert is disposed in the interior of the underdrain block. The insert includes force-transmitting buttresses spaced along an exterior of the insert that contacts the two side walls of the underdrain block and act to transfer downward forces acting on the top wall of the underdrain block and internal fluid forces acting on the insert to the side walls of the underdrain block. The force-transmitting buttresses can also direct hydraulic flow.