Ciliwung delta (Jakarta)

The Ciliwung delta, for the largest part occupied by Indonesia's capital city Jakarta, faces rapid subsidence caused by excessive groundwater extraction and construction load. The resulting flood risk and land loss widen the gap between the rich and the poor as some people do not have the resources to adapt to the changes.

Urgency 

Land subsidence is a problem that the inhabitants in the delta have been facing and adapting to for the last 20-30 years. Academic publications from the last 5 years show that Jakarta is currently the fastest sinking city in the world. This raised the sense of urgency at the national government, and since then it is increasingly included in political agendas. 

Current policy approach 

Road map 

As a national approach, the government’s administrative functions and therefore 2.5 million people will be moved to East-Kalimantan, Borneo, to decrease the water demand in Jakarta. Furthermore, in cooperation with Wetlands International and others, the local government of Jakarta has established a road map of adaptation and mitigation strategies. Guided by this roadmap, they have developed a map of land subsidence risks in the coastal lowlands and are currently working on monitoring programs and developing short-term solutions such as building dikes (see Giant Sea Wall), raising houses and infrastructure, and artificially recharging aquifers. In the long term, the local government aims to integrate land subsidence in spatial planning and water management, enforce related laws, and raise awareness.  

Restricting factors 

Until now the implementation of these strategies is challenging due to a lack of funding and decision-making, given the multitude of approaches being proposed by the academic world and the many involved interests. In addition, certain important measures such as the regulation of groundwater extraction are not effective since they are undermined by a few powerful people.

Recommendations

There is an urgent need for a comprehensive approach to encourage the implementation of adaptation and mitigation measures

Erlis Saputra, postdoctoral researcher on the governance and socio-economic impact of land subsidence in Jakarta, says, “There is an urgent need for a comprehensive approach to encourage the implementation of adaptation and mitigation measures”. This means that the needs of the people and their decreasing income and adaptation capacity should be a major concern, and therefore local stakeholders need to become involved in policy-making processes. Erlis Saputra also sees the need for improved cooperation with authorities in the upstream catchment to enhance the quality of the river water, which can help reduce the rate of groundwater extraction in Jakarta (‘ecosystem approach’).