construction of 1150 cum capacity 20 mtr. staging height r.c.c. over head water reservoir as per departmental design, drawing and specification including bored pile & pile cap at ( zone- xxv ) i.e. jhikra& laying of distribution system, providing fhtc, construction land development, construction of office cum guard room and switch cum chlorine room, boundary wall, surface drain and other allied works within the jurisdiction of ( zone-xxv ) under surface water based water supply scheme for arsenic affected areas of habra-gaighata & adjoining mouzas under north 24 parganas district project” under barasat division, p.h.e. dte. gaighata block, part-g.