The MBBR is a complete mix, continuous flow through process which combines the benefits of fixed film and suspended growth processes. Benefits include increased treatment capacity, improved settling characteristics, enhanced process stability, and reduced sludge production. The process can either be used as a 1) pre-treatment system ahead of an existing activated sludge system for increased organic matter removal, 2) stand alone biological treatment process for BOD removal, nitrification and/or denitrification or 3) a retrofit of an existing activated sludge processes to help increase overall nitrification capacity of the existing system. The MBBR process uses small plastic carrier elements to provide sites for bacteria attachment in a suspended growth medium. The carrier elements allow a higher biomass concentration to be maintained in the reactor compared to a suspended growth process, such as activated sludge. This increases the biological treatment capacity for a given reactor volume. The carrier elements can be installed in either an anoxic reactor or aeration basin. A screen or sieve assembly with 5 mm slot openings is used to retain the carrier elements in the reactor. The effective open area of the screen is sized to provide less than 2 inches of headloss. However, the process does not require backwashing of the retention screens which retain the carriers.The carrier elements are continuously kept in suspension by either a mixer or an aeration system. The agitation pattern in the reactor is designed to provide an upward movement of the carriers across the surface of the retention screen which creates a scrubbing effect to prevent clogging. Coarse bubble and jet aeration are typically used to provide oxygen for an aerobic reactor. Reports using fine bubble aeration in an MBBR system indicate the media cause the bubbles to coalesce, thereby reducing oxygen transfer efficiency. Jet aeration is recommended for new installations due to its intense mixing and improved oxygen transfer efficiency when compared to coarse bubble. MBBR waste water treatment plant can be described as a low space requirement (Compact Plant) with efficient operation. After screening and collection of raw sewage in RSCS (Raw Sewage Collection Sump), the sewage is treated in MBBR, in which the organic digestive micro-organisms get attached to specially design plastic media called AGM (Attached Growth Media) or moving bed media. The AGM bio media become the carriers that build fluidized bed in waste water. Proper arrangement is given to AGM for maintaining it in fluidized condition (or Aerated Condition). The biofilm grows on the bio media surface and moves along with the waste water inside the reactor chamber known as biomass. The efficiency of biomass in reducing the organic load in waste water is responsible for the successful operation of MBBR system. The movement of AGM is caused by efficient aeration system by means of diffusers and the system is well designed according to the effluent requirement. Treated water from bio reactor is allowed to settle in clarifier tank. Supernatant from clarifier is passed through series of filters (PSF & ACF) followed by disinfection system and collected in TWST (Treated Water Storage Tank). Treated water is used for flushing and gardening.