Mangroves Against Wave Overtopping at Breakwaters and Revetments in Jakarta Fishing Port

By the 1970s, Jakarta’s historic fishing port could no longer meet Indonesia’s growing fishery demands. The old Batavia market and port struggled with inadequate infrastructure, poor handling capacity, and limited resilience to coastal environmental pressures. Responding to these challenges, the Indonesian government partnered with Japan to finance feasibility studies and construction of a modernized Jakarta Fishing Port (JFP) in the 1980s. Additional improvements followed throughout the 1990s and early 2000s.

Nature-based measures were introduced across successive phases rather than in a single period. The tidal seawater purification system (Orishimo Method) was proposed during the Phase IV upgrading (1993 to 2002), and the rehabilitation and improvement project (2004 to 2012) used bamboo pile and mat foundations to support revetments and breakwaters on soft seabeds, with mangrove forest used as part of the wave-reduction function around port structures (JSCE, n.d.; Oka, Orishimo and Nagano, 2004). These mangroves were strategically placed to dissipate wave energy, limit overtopping impacts on quay walls, reduce erosion, and enhance water quality. While literature indicates these nature-based measures were initially effective, continued land subsidence and higher-than-expected sea level rise have since reduced their long-term functionality (World Bank, 2025).

JSCE reports that construction costs were lower because local materials and manpower were used, and that lowering the top elevation of breakwaters and revetments, with mangroves providing part of the wave reduction, reduced construction costs (JSCE, n.d.).

JSCE also reports reduced maintenance costs, and the purification system uses tidal range fluctuation to exchange and purify seawater (JSCE, n.d.). Habitat, recreation and energy-saving outcomes have not been sourced and are not claimed here.

However, these benefits must be viewed through the lens of ongoing risks. Jakarta faces some of the world’s highest rates of land subsidence, coupled with sea level rise. These pressures may challenge the effectiveness of mangrove-based defenses and highlight the need for continuous adaptation and planned reinvestment.