A water intake and pretreatment system (10) comprising an inlet for delivering water from a natural source to a reservoir (12); said inlet to reservoir having a net screen (16) to prevent entry of organisms above a predetermined size and including a one-way gate (30) to allow organisms to exit the reservoir; said reservoir further comprising a granular filter media for water and algae filtration; and a drainage layer for removal of filtered water from the granular filter media to a drainage outlet. A local backwashing apparatus (40) is included for localized backwashing of the granular filter media.

Vaults, boxes, chambers, systems, and methods of treatment systems to capture pollutants from storm water runoff and prevent the conveyance of these pollutants from entering a receiving water body or landscape area, which is designed to be a part of a local permanent storm water drainage infrastructure. The system enhances the removal efficiency of almost any type of filtration media by increasing contact time between storm water runoff and the media, and also offers an easy and inexpensive method for serving the media, without having to remove or replace the media. A media filter can include a bottom screen, a media layer, and at least one top lid that can be opened to allow for backwashing of the media layer without removing the media layer from the filter. A servicing system can include pivotal spray heads to pivot to parallel positions over a sloped floor to flush debris toward easy to reach locations to be vacuumed, and vertical spray heads which can break up debris bridges.

A nozzle is disclosed for use within a filter for inputting a jetting stream into the filter media to clean the filter media. The nozzle comprises an inlet for communication with a jetting stream source, and a plurality of plates stacked parallel and abutting one another. The plurality of plates comprises at least a top plate and a bottom plate, one of the plates having an aperture through the center thereof for receiving the jetting stream, wherein between adjacent plates at least one space is provided extending from the outside edge of the plates to the interior of plates and in fluid communication with the aperture for channeling the jetting stream radially outward from and substantially parallel with the longitudinal plane of the plate.

An apparatus for removing impurities from water and/or wastewater and a method of installing a fluid distribution system in the apparatus. In the most preferred form of the invention, the fluid distribution system is an air scour system for directing air through the filter bed to assist in cleaning of the filter bed to remove impurities trapped in the filter bed during a service run. In the most preferred form, the method of installing the fluid distribution system in the filter bed is performed by imparting a force to the filter bed to permit the fluid distribution system to be installed in the filter bed without removing media. The fluid distribution system is preferably configured to permit the fluid distribution system to be readily installed in the filter bed and at an optimum orientation.

An underdrain assembly for filtering particulates from a fluid having an upper structure connected to a bottom plate. At least one flow control vane is positioned between the upper structure and the bottom plate for directing and managing fluid flow through the assembly. The upper structure can have first and second filtration members, the second filtration member positioned between the first filtration member and the bottom plate. The second filtration member can have a shape that restricts fluid flow within the underdrain. The underdrain can have air and water inlets. The water inlet can have an end with a plate covering an upper portion thereof. The end can also include an opening having an angular cut forming an angle with respect to a longitudinal axis of the water inlet. Thus arranged, air is prevented from migrating out the water line. A resilient mounting arrangement for the underdrain is also disclosed.

A piezoelectric deionization system uses a piezoid bed made up of multiple piezoids for deionization of a working fluid containing charged particles, ions, and/or ionic complexes. The working fluid may be salt water in various embodiments. A uniaxial compressive force is applied to the piezoid bed causing a piezoelectric effect in the piezoids, resulting in a piezoelectric field generated by each particle, which attracts charged particles, ions, and/or ionic complexes contained in the working fluid. The piezoid bed is contained in a closed chamber to which the uniaxial compressive force is applied. Monocrystalline quartz particles or another suitable piezoid, natural or synthetic, may be used. A fluid is used to purge the piezoid bed of charged particles, ions, and/or ionic complexes after the piezoid bed becomes saturated through use. The working fluid may be used to purge the piezoid.

A coated granular filtration medium is formed by the deposition of an electrolyte layer onto core particles. The electrolyte layer comprises a cationic polyelectrolyte. The coated granular filtration medium provides a synergistic combination of filtration and in situ coagulation that enables efficient, effective, and economical decontamination of industrial and other wastewaters.

A water treatment filter backwash process control system, comprising a control system that receives filter level data and filter backwash turbidity data. The control system having a filter level set point, wherein the filter level set point corresponds to a desired filter media bed expansion. The control system having a filter backwash turbidity set point, wherein the control system controls the filter backwash process by, while monitoring the filter backwash turbidity, sending one or more output signals that are used to control a backwash inlet liquid flow in order to maintain a desired media bed expansion, and stop the backwash inlet liquid flow when the filter backwash turbidity set point is reached.

In this infiltration intake system, a structural body integrally includes a waster discharge direction control portion controlling a discharge direction for wastewater discharged from a filter toward a raw water side at a backwash time with a backwash mechanism portion in a prescribed wastewater discharge direction.

A wastewater filter includes a vessel having a bottom and a side wall that cooperate to define a filter space. A first filter media is positioned within the filter space to define a first media layer, and a second filter media different from the first filter media is positioned within the filter space above the first media layer to define a second media layer, the first media layer and the second media layer cooperating to define an interface plane. A draft tube is positioned within the second media layer and has a first end positioned a first non-zero distance above the interface plane, and a second end disposed a second non-zero distance from a top surface of the second media layer. A backwash fluid line is positioned to inject a backwash fluid into the first filter media, and a backwash gas line is positioned to inject a backwash gas into the draft tube.