Operation & Maintenance Of Civil Work Of 13.89 Mld Capacity Surface Water Based Piped Water Supply Scheme At Part -Iii (Northern Sector) In Nadia District Including Raw Water Intake, Raw Water Main, Water Treatment Plant, Clear Water Main, Distribution System Of 04 (Four) Zones All Complete Including Supply Of Manpower, Material And Chemical Etc For The Period Of 06 Months = 181 Days.