The Republic of Indonesia, the world's fourth most populous country and the largest economy in ASEAN, continues to experience steady economic growth. However, Jakarta, its capital city with a population exceeding 10 million, has a sewerage coverage rate of only around 12%, resulting in serious environmental challenges such as river and groundwater pollution. To address these critical and urgent challenges, the city has launched the "Jakarta Wastewater Management Master Plan in DKI Jakarta," which divides the city into 15 zones for phased development of sewerage infrastructure aimed at improving public health and the urban environment.

The Zone 6 contract covers the construction of a sewage treatment plant in a densely populated area, which includes numerous commercial facilities such as shopping malls. The plant will have a treatment capacity of 47,500 m³/day (Phase 1 planned population: 301,000; Zone 6 overall planned population: 1,465,000). The project will adopt the Integrated Fixed Film Activated Sludge (IFAS) system, which enables higher concentration of microorganisms in reaction tanks compared to conventional methods, enhancing treatment efficiency. Following the precedent set in Zone 1, the project will also utilize the pneumatic unmanned caisson method, a well-established technology in Japan that enables caissons to sink and settle into place using their own weight. Z6 OWJ2 JV will undertake the project on a full turnkey basis: Obayashi and WIJAYA KARYA will be responsible for the civil engineering works, while JFEE and JAYA KONSTRUKSI will handle the electrical and mechanical works.

Obayashi and JFEE will continue to utilize Japanese technology to promote high-quality infrastructure development, thereby contributing--among other initiatives--to improving sewerage coverage rates in Asian countries, including the Republic of Indonesia, and working toward the enhancement of people's living environments and the realization of a sustainable society.