GATE Civil Engineering (CE) 2012 Solved Paper

A town is required to treat 4.2 m3/min of raw water for daily domestic supply. Flocculating particles are to be produced by chemical coagulation. A column analysis indicated that an overflow rate of 0.2 mm/s will produce satisfactory particle removal in a settling basin at a depth of 3.5 m. The required surface area (in m2 ) for settling is