Indonesia Plans Giant Sea Wall for October 2026, But Design Details Remain Unknown

Central Java province in Indonesia is slated to begin construction on a massive sea wall in October 2026, a project intended to protect its northern coast from rising sea levels and severe land subsidence. However, officials admit they have not yet received detailed engineering designs for the "giant sea wall."

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Giant sea wall this is planned by the Authority (North Coast) to break ground around October. That's all the construction, what its form is, then where its location is, how far, we also haven't gotten certainty on how many kilometers. Including where the location is.

Yusmanto, head of the Central Java Regional Development Planning Agency (Bappeda), stated that while the North Java Coastal Management Authority (BOPPJ) plans to break ground, the specific construction methods, exact locations, and total length remain unclear. Bappeda has recommended prioritizing the Teluk Semarang area for the initial phase, followed by eastern coastal areas like Demak, and then western regions such as Pekalongan and Tegal.

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If we suggest, propose, and strongly encourage that the one in Teluk Semarang be completed first.

The urgency for such a project is underscored by alarming rates of land subsidence. In Semarang, the land sinks an average of 12 centimeters per year, while Demak and Pekalongan experience sinking of up to 16 centimeters annually. This phenomenon, coupled with rising sea levels, poses a significant threat to coastal communities.

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So the land is sinking, the sea is rising. But the worst are those points starting from Tegal, Pekalongan, then Semarang, Demak.

Officials are studying the technical aspects of construction, particularly for Teluk Semarang, which is characterized by mud rather than sand. Lessons are being drawn from the Semarang-Demak toll road project, which reportedly used millions of bamboo poles and still experienced ongoing sinking. The sea wall is planned to be built 12 miles offshore, presenting its own set of construction challenges. Yusmanto noted that the design and construction methods will likely differ along the extensive coastline, from Serang to Banyuwangi, adapting to the unique geological conditions of each area.

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So if the Authority works (to build the giant sea wall) from Serang to Banyuwangi, the construction must be different.