The microbiologists separate bacterial mixed populations into individual species for study. The waste water resulting from various human activities (domestic, agricultural and industrial) is technically referred to as sewage. The sewage is mostly composed of organic and inorganic compounds, toxic substances, heavy metals and pathogenic organisms. The bacterial flora was isolated from the serial diluted sewage sample which was collected from the Naga drain. Microscopic examination, physical and morphological characteristics, biochemical tests of the bacterial growth was investigated. During the investigations, the following genera, viz. Enterobacterium sp., Salmonella typhimurium, Pseudomonas sp., Shigella sp. were isolated. The above mentioned genera were concluded to be enteric gram-negative bacteria, which are pathogenic and resistant to multiple drugs.
