Evaluation of causes of a massive land subsidence and ef-fectiveness of measures to control of them in Jakarta and other cities

Jakarta, 27 November 2018 -- A discussion to evaluate the cause of land subsidence in Jakarta was held in the Ministry of Public Works, Republic of Indonesia premises. Several experts from various technical background were presented their findings. The discussion divided into 3 session, namely: to understand the factors behind the caused of land subsidence, to understand the effects of land subsidence, and mitigation efforts. keywords: Jakarta, Land subsidence, groundwater extraction

Photo: Dr. Sutardi from Indonesia Water Partner-ship (at Front right) presenting his finding

Land subsidence is a threat that is faced by many urbanized delta cities around the world. As one of the mega cities, Jakarta is facing common problem. A few studies pointed out that the cause of land subsidence in Jakarta was due to massive ground water extraction, massive infrastructure development, and natural geological char-acteristic.
The workshop was held in order to understand not only the main cause of the land subsidence but also to learn and exchange about the experiences and lesson learned on how to mitigate and to adapt from experts from different technical background. Among these experts, Mr. Peter Letitre from Deltares, Mr. Barry Beagen from Kotakita, and Mr. Takeshi Watanabe from Yachio/JICA were able to share their experiences and research regarding land subsidence in several city in Indonesia.
In overall, several findings were discussed, such as:

  • General causes of land subsidence: natural loading, building loading, excessive abstraction of ground water and tectonics.
  • Mitigation recommendation to slow down or stop the land subsidence
  • Alternative solution to the ground water extraction to fulfill domestic and sectoral needs.

One take away key message from this workshop was that we need to stop debating on the causes of the land subsidence and start to move forward to mitigate and adapt. Adaptation itself is important, but mitigation is equally as important. We cannot just build a higher wall to prevent floods as a mean of adaptation. Therefore, mitigation effort become important.
This workshop was organized by Indonesia Water Partnership and in collaboration with JICA, Deltares, Ministry of Public Works, Pancasila University, Kotakita, NCICD secretariat, and Gerakan Ciliwung Bersih.
This workshop was the first of serial workshops that aims to pro-duce a multi stakeholder position paper on land subsidence mitiga-tion and adaptation. in 2019, at least 3 workshops will be organized in order to realize multi-stakeholders position paper. AW