Biofilms, are defined as communities of microorganisms that grow embedded in a self-generated matrix of exopolysaccharides and adhered to an inert surface or a live tissue. They are formed 95% of water, the rest are microbial cells and their derivatives.In the first works on the biofilm structure, one of the questions that arose was how bacteria within the biofilm could have access to nutrients and oxygen. Studies demonstrated that the architecture of the biofilm matrix is not solid and has channels that allow the flow of water, nutrients and oxygen, even in the deeper layers of the biofilm. The existence of these channels does not avoid, however, that inside the biofilm can be found different environments in which the concentrations of nutrients, pH, or oxygen are different. This increases the heterogeneity of the physiological state in which the bacterium is found within the biofilm and makes difficult its study for it gives it a higher resistance. The stages for biofilm formation are: 1. Adhesion; 2. Extracellular matrix synthesis: grouping by chemical self-inducing signals (quorum sensing) and secretion of exopolysacharides to form the biofilm matrix; 3. Maturation and dispersion is the way of colonizing new sites. which can be transferred by water, environmental contamination, or fomites. The bacterial growth on the walls of the pipes is a very common habitat for potentially pathogenic bacteria. The presence of microorganisms in drinking water and the formation of biofilms in the distribution water systems produce bacteriological contamination and these associations may occur among bacteria, fungi, and protozoa, granting a higher resistance and pathogenesis to the biofilm. The Journal of Public Health of Mexico (2011), and the National Institute of Health, USA (2003) published that in 75% to 80% of bacterial diseases infectious, biofilm intervene.