From Korea to the UN: Water management philosophy gains global recognition
Han Moo-young
On June 5, World Environment Day, a Korean-born water management philosophy called “MoMoMo” was officially featured in the United Nations Stakeholder Consultation Summary Report for the upcoming 2026 U.N. Water Conference in Abu Dhabi.
MoMoMo, short for “Management of all water, by all, for all,” promotes decentralized, community-led and inclusive approaches to water management. The philosophy is rooted in Korean heritage — including King Sejong’s 15th-century rain gauge (cheugugi) network and the national principle of "hongik ingan" (benefiting all humankind) — and blends scientific innovation with ethical governance.
Unlike conventional centralized systems, MoMoMo emphasizes local participation and education, especially among youth and marginalized communities. It aligns with global calls for climate resilience, gender equity and water justice. The core message is simple: Everyone is a water manager and every drop counts.
I proposed this concept through my nongovernmental organization, Rain For All, and it was adopted after years of field implementation in Southeast Asia. In the Mekong region, more than 20 Rain Schools have been successfully established. These schools not only serve as educational hubs but also demonstrate how rainwater harvesting can improve daily life and build resilience in vulnerable communities.
In Cambodia specifically, the Rain School Initiative has been formally integrated into the national education and water policy. The Cambodian Ministry of Education, Youth and Sports has expressed a commitment to expand the model nationwide, aiming to build 1,000 Rain Schools across the country. These schools engage students and teachers in practical learning — monitoring rainfall, testing water quality and promoting water-saving habits. Rain becomes more than a resource; it becomes a subject of science.
Beyond Cambodia, Rain Schools and Rainwater for Drinking (RFD) systems have been introduced in other Southeast Asian countries and Pacific Island nations. These efforts respond not only to water scarcity but also to a broader set of climate challenges.
We are currently piloting a new model of decentralized water service: the rainwater drinking cluster. This approach centers around a Rain School equipped with mobile RFD systems — compact, electricity-free purification units capable of producing drinking-quality water. Households in surrounding villages draw from this cluster, creating a low-cost, community-scale water network without the need for underground infrastructure. It is an alternative to piped water systems and has proven useful in disaster-prone areas.
The broader implications of MoMoMo are significant. It offers practical solutions to pressing issues like wildfires caused by dry landscapes, groundwater depletion from overextraction and the breakdown of urban water cycles due to impermeable surfaces. MoMoMo even offers strategies to mitigate urban heatwaves through improved moisture retention and landscape design, aligning with both mitigation and adaptation goals under climate policy.
MoMoMo’s recognition in the U.N. report reflects a shift in global thinking. It validates the role of traditional wisdom, civic engagement and cultural values in shaping sustainable development. It also underscores Korea’s potential to lead in environmental innovation — not through megaprojects, but through community-based, ethical and educational approaches.
Moving forward, we aim to build a global Rain School network, collaborate with international partners and organize official sessions and side events at the 2026 U.N. Water Conference. We believe that the philosophy of managing all water, by all, for all can inspire new policies, new partnerships and a renewed sense of responsibility for our shared water future.
Water connects us. And when managed with wisdom, it can heal divisions, restore ecosystems and bring dignity to communities worldwide.
Han Moo-young is professor emeritus of civil and environmental engineering at Seoul National University and founder of Rain For All, a U.N. ECOSOC-accredited nongovernmental organization.