Sabiha Gokcen International Airport (SAW) is located in the Anatolian side of Istanbul. SAW departing passengers’ deck structural system consists of steel beams which are supported on seismic isolators placed on concrete pedestals. The client requested to investigate the experienced problems related to existing drainage system and corrosion issues. After investigation it is observed that the drainage system was not working properly and as a result, the deck was corroded. Departing passengers’ deck is used very intensely. Therefore, three alternative projects are prepared by considering both cost and business interruption matters. In addition, the technical specifications for maintenance and repair were prepared to serve throughout the life-cycle of the structure.