bids are invited for operation and maintenance of water supply systems - supply of 110mm dia 6kg cm2 pipe and making foundation of hand pump , operation and maintenance of water supply systems - supply of 32 mm dia g i pipe of medium class , operation and maintenance of water supply systems - gl to 20m b g l , operation and maintenance of water supply systems - 20b g l to 40m b g l , operation and maintenance of water supply systems - 40b g l to 50b g l , operation and maintenance of water supply systems - lowering of pvc assembly compressing of pvc ribbed complete in all , operation and maintenance of water supply systems - installation of india marka ii hand pump assembly in to pvc assembly as per instruction of engineer , operation and maintenance of water supply systems - development of bore by pumping with pump or by manual contr , operation and maintenance of water supply systems - hiring charge for necessary t&p and equipment required for installation of hand pump complete