In the water industry, biofilm can be described as a thin layer of cells made up of microorganisms, such as bacterium or fungus, which are held to the surface of pipes by slime.In the last few years, biofilm has been of great interest, not only to distribution operators, but to people in the medical and educational fields. Biofilm can literally be found everywhere. The slick layer you feel on your teeth in the morning after waking up is a form of biofilm called Dental Plaque.
Every distribution operator has seen biofilm; it is the slime layer you see inside distribution piping. Once biofilms are formed they can be the cause of a wide range of water quality and operational problems. Biofilms can be responsible for loss of distribution system disinfectant residuals, increased bacterial levels, reduction of dissolved oxygen, taste and odor changes, red or black water problems due to iron or sulfate-reducing bacteria, microbial-influenced corrosion, hydraulic roughness and reduced materials life.They also can be the home to several dangerous diseases (ie. E. Coli, Pseudomonas, Sarcina) that can hurt the customers you serve. Once attached to the pipe walls, biofilm cannot be removed easily. Maintenance of a disinfectant residual throughout the distribution system may help to maintain the integrity of the distribution system by inactivating microorganisms in the distribution system, indicating distribution system upset and controlling biofilm growth.
The following link is a video that provides a brief overview of biofilm. http://www.youtube.com/watch?v=twxPyvdc-EE