annual operation and maintenance of pumping stations & reservoir and reservoirswhich are at the top of the various estate of hda building, electrical installations, allied facilities with internal distribution pipeline network, valves and special including all supply materials and labour etc. for water supply to the flats at priyambada housing estate ( 40 flats’ complex , 44 flats’ complex, 18 flats’ complex and 197 flats’ complex ) at basudevpur, satish samanta bhawan atcity centre, haldia bhawan & ceo residence cum office at haldia, township, administrative building at basudevpur, super market building at durgachak