March 2, 2026

Site overview – completed plant undergoing site office demolition and land reinstatement.
On the drive from the airport into Surabaya’s city centre, the road occasionally hugs the banks of the Kalimas river. Kalimas means “golden river” in Javanese, a reminder of the river’s historic role as a trading gateway for the Majapahit kingdom, which ruled much of Southeast Asia from the 13th to 15th century.
Today, the river continues to shape this city – it is the source behind Surabaya’s newest water treatment plant.
I visited IPAM Kilarang Pilang IV shortly after commissioning, curious to see how a 1000 litre-per-second project could be delivered in just over ten months. Standing on site, it was hard to imagine that this operational plant was just an empty field when the contract was awarded to BW Water early last year. Today, the plant helps strengthen water reliability for the residents of Surabaya, producing drinking water from a river known for its high turbidity, ammonia, iron, and organic content.
I met the project team who had navigated the months of intensity. What struck me most was how understated their reflections were. I felt a quiet confidence that comes from sustained effort. The Project Manager, Reza Rafiq, shared how close collaboration and coordination with our suppliers, the client and the contractors were key to successful execution, enabling our team to complete equipment installation in six weeks.
This experience perfectly illustrates how trust gives speed. When there is an understanding that we are all working towards a shared common goal – delivering reliable water supply to Surabaya – decision-making accelerates. Just like a river which appears to flow calmly and smoothly, carried by the strong currents that run beneath.
This new water treatment plant now stands as a continuation of the long relationship between a city and its river, silently whispering that progress is not a single leap, but a steady and reliable current.
This blog is written by Joey Chiang, BW Water’s global marketing communications manager.
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