Bacterial populations thrive almost anywhere.  Bacteria are considered as natural component of bodies of water like lakes, rivers, and streams.  Bacteria are a numerous and diverse group of organisms that shape an invisible link at the base of aquatic food chains. As examined carefully under the digital binocular microscope there are more than 60 genera of bacteria present in aquatic systems.  The numbers can range from forty thousand to over twelve million bacterial cells in a small amount of water which can barely cover the bottom of a coffee cup. The huge numbers of these microorganisms can have a big impact on processes that occur in aquatic ecosystems such as carbon, nitrogen, and sulfur transformations. Bacteria can likewise affect the quality of water by controlling the amount of oxygen in the water.   Bacteria can cause diseases on aquatic organisms and in human beings.
Indicators of Bacteria in Water
Various kinds of bacteria can indicate that the water supply has been contaminated.
Fecal coliform bacteria belong to a subgroup of coliform bacteria.  This type of bacteria are used to establish the first microbial water quality standards. The fecal coliform bacteria have the capacity to grow at an elevated temperature of 44.5 C which separates these bacteria from the total coliforms.  They are known as   accurate indicator of fecal contamination by warm-blooded animals. As examined under the digital binocular microscope, fecal coliform bacteria are detected by simply counting the pink-red colonies which grow on a 0.65 micron filters placed on mFC agar incubated in a 44.5 C oven for 22-24 hours. The presence of fecal coliforms in water is an indication of fecal contamination   by a warm-blooded animal.  However, studies have found no statistical relationship between fecal coliform concentrations and swimmer-associated sickness.
Under the digital binocular microscope, Escherichia coli (E. coli) is a rod-shaped bacterium.  They are commonly found in the gastrointestinal tract and feces of warm-blooded animals. As a member of the fecal coliform group of bacteria, E. coli is distinguished by its inability to break down urease. The presence of E. coli   in freshwater is e determined by counting the number of yellow and yellow brown colonies growing on a 0.45 micron filter placed on m-TEC media and incubated at 35.0 C for 22-24 hours. The addition of urea substrate confirms the E. coli colonies. The presence of this bacterium provides direct proof of freshwater contamination from warm-blooded animals. E. coli is the known cause for various diseases like meningitis, septicemia, urinary tract, and intestinal infections. There is a strain of E.  Coli (E. coli 0157:H7)   recently discovered which can cause severe disease and may even be fatal in small children and the elderly.
Another indicator is the Enterococci.  Enterococci are a subgroup of the more general group of fecal streptococci bacteria. These bacteria are common inhabitants of the human intestinal tract. The numbers of enterococci are determined with the use of the digital binocular microscope by counting pink to red colonies that have a black or reddish brown precipitate on the underside of a 0.45 micron filter placed on m-E media for at 41 C for 48-50 hours, then on EIA media for 20 minutes. Enterococci also are a preferred indicator organism for freshwaters and marine waters used for recreation. Enterococci bacteria have been found to be superior to fecal streptococci as a predictor of swimming-associated gastroenteritis. Studies have shown that numbers of enterococci in fresh or marine surface waters are associated with an increased rate of swimming-associated gastroenteritis.
Clostridium perfringens when examined under the digital binocular microscope is an anaerobic, spore-forming, rod-shaped bacterium. It is   found at high concentrations both in human and animal feces as well as sewage. Clostridium perfringens must be analyzed and studied under anaerobic conditions by highly trained technicians. These bacteria are useful as a water-quality indicator since they form spores that are more resistant to disinfection and environmental stresses as compared to the other indicator bacteria. Clostridium perfringens may be used as a surrogate for stress-resistant organisms.
Diseases Caused By Bacteria in Water
There are various diseases caused by pathogenic bacteria in water like cholera, dysentery, shigellosis and many more.
Man is the main cause of water contamination. Man can also prevent water contamination by adapting a clean and healthy lifestyle.  After all, cleanliness is next to Godliness.Read More