Jakarta. Indonesia risks significant economic losses if a long-planned giant sea wall along the northern coast of Java is not realized soon, Chief Infrastructure and Regional Development Minsiter Agus Harimurti Yudhoyono said on Monday.

The coastal stretch, known as Pantura, plays a critical role in the country’s economy, contributing about 27.53% to gross domestic product, or roughly $368.4 billion (Rp 6.38 quadrillion), AHY said at the Maritime Affairs and Fisheries Ministry in Jakarta.

“It is not only important for Java, but its contribution to the national economy is also significant,” he said.

Pantura hosts key economic infrastructure, including five major industrial growth centers, around 70 industrial estates, 28 designated industrial zones and five special economic zones. AHY said the proposed sea wall is essential to safeguard these assets from mounting environmental threats.

Indonesia plans to build a coastal defense stretching roughly 500 kilometers along the northern shoreline of Java — home to more than half of the country’s population — though some estimates suggest it could extend beyond 700 kilometers. With an estimated cost of $80 billion, the government is pursuing a public-private partnership scheme and actively courting foreign investors.

President Prabowo Subianto pitched the project to China in 2025, but Jakarta has since broadened its outreach. Previous reports have pointed to interest from countries such as the Netherlands, known for its advanced water management systems including the Afsluitdijk, as well as South Korea, home to the Saemangeum Seawall — one of the world’s largest coastal barriers — and Japan, which has significantly reinforced its seawall infrastructure following the 2011 Tōhoku earthquake and tsunami.

“We must ensure there is no disruption to economic activity, and more importantly, prevent potential loss of life if no action is taken today,” he said.

The minister warned that conditions along the coast will continue to deteriorate without government intervention. Land subsidence, particularly severe in Jakarta and Semarang, is occurring at rates of between 1 and 20 centimeters per year, compounding the risks.

At the same time, rising sea levels driven by global warming are adding pressure, with waters increasing by an estimated 0.8 to 1.2 centimeters annually. This combination heightens the threat of tidal flooding, which can damage homes, infrastructure, and coastal communities.

“This is a double pressure, rising sea levels and land subsidence, that can trigger recurring tidal floods, destroy property, and potentially lead to more severe disasters,” AHY said.

Projections to 2050 show worsening coastal inundation if no concrete measures are taken, he added, underscoring the urgency of addressing environmental degradation in the region.

The stakes are high for local populations. The Pantura region spans 20 regencies and five cities, home to around 55 million people, with about 26% living in vulnerable coastal areas.

“That is why this is an urgent issue that should mobilize all of us,” AHY said.

Indonesia plans to build a coastal defense stretching roughly 500 kilometers along the northern shoreline of Java, home to more than half of the country’s population, though some estimates suggest the structure could extend beyond 700 kilometers.