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One of the production facilities in PT Pertamina Hulu Energi’s ONWJ (PHE ONWJ) consisting of four bridge linked platforms and flare has been experiencing subsidence over several years. It was considered necessary to raise the topside structure of the four bridge-linked platforms to ensure a continued safe operation of the Lima complex until the end of its production life. PHE ONWJ engaged a specialist contractor to design a jacking system to raise all subsiding platforms and associated bridges simultaneously with multiple synchronized hydraulic jacks without removing the bridge connections between the platforms. Given the unique condition of the existing facilities and considering that simultaneous raising is a nonconventional method, a holistic engineering approach was applied. This paper provides an overview of the engineering approach with regard to the design of the structural raising system, the mechanical equipment, and the control system. The structural raising system has been designed in accordance with the raising sequence and with the purpose of minimizing construction time, yet being structurally sound. The mechanical equipment has been designed in accordance with the raising sequence and with sufficient redundancies to ensure reliability. The control system has been designed for a simultaneous raising of the Lima complex within a specified criteria of operations. All the components shall work as a system for a simultaneous raising of the Lima Flow Station to reach its target elevation for a continued safe operation purpose.