Semarang is a coastal city of more than 1.6 million people and is considered a global hotspot for land subsidence due to groundwater extraction. Large parts of the city are below sea level already. The Banger polder Project, Launched in 2016, aimed to reduce flood risk in the area by developing a technically well-functioning polder system, creating a sustainable water management organization and improving stakeholder participation. Stakeholder engagement is critical for the financial and operational support of the polder system. However, the results show that Semarang’s stakeholder engagement scores the lowest on the OECD ladder of stakeholder engagement. This paper assesses the engagement of various stakeholder representatives in the water management organization and identifies key strengths, weaknesses, opportunities, and threats to the polder system through a SWOT analysis. The main threats are the lack of awareness among residents, that leads to solid waste being disposed of in waterways, the lack of adequate management and funding, and uncertainty about the future maintenance system.