The wastewater generation at Putrajaya was collected by a series of sewer networks that eventually lead to two centralised sewerage treatment plants, STP 1 and STP 2. The preliminary site investigation of the sewer networks by PJH had concluded the presence of groundwater infiltration and siltation problems at STP1 through the sewer networks. Therefore, an open tender was called by PJH to carry out 100% CCTV on all laid sewerlines and rectify any sewer defects which caused the leaking problem. Asia Baru Construction Sdn. Bhd. was successfully in its bid and the following works were carried out: