The importance of sewer biofilms

In spite of being under ground and out of sight, sewers are important parts of the urban infrastructure for transporting used, contaminated water for safe treatment. Within sewers, during the transport of waste water, processes take place, transforming the chemical components of the waste water. These processes are largely carried out by bacteria, a significant part of which live in biofilms. These microbial processes impact the sewers by causing odor and corrosion of the sewer pipes, leading to the need costly repair and control strategies. The biofilms may also impact the environment by contributing to greenhouse gasses in the atmosphere and pollution in natural aquatic environments. However, improved understanding of the function of biofilms and the novel techniques and approaches for manipulating biofilms may provide us with strategies for controlling these problems. Moreover, such advances may allow us to design in-sewer biofilms for beneficial purposes such as in-pipe treatment of waste water, potentially leading to decreased environmental impact. (C) 2016 The Authors. WIREs Water published by Wiley Periodicals, Inc.