The present case study is focused on performance evaluation of a Reverse Osmosis (RO) membrane based pilot plant to treat the ground/surface drinking water sources polluted by flood, rivers and/or canals. The RO plant was designed, fabricated and then operated with polluted water. Two feed water samples having a TDS of 2.000 mg · L−1 and 10.000 mg · L−1 respectively, were taken and analyzed for physical, chemical and microbiological contaminants. The RO plant was run once through over a span of 100 hrs at an operating pressure of 15 bar. TDS rejections were found to be more than 94% while permeate flux was measured to be 25.82 L · m−2 · hr−1 to 40.55 L · m−2 · hr−1. Results show that RO plant has a potential to remove physical, chemical and microbiological contaminants like Total Coliform and E. Coli in one step.