Surabaya is one of 50 finalists from 33 countries that will receive $50,000 and support to test breakthrough ideas for improving Clean water, Waste management & sanitation, , Economic and Workforce Development.

Surabaya aims to improve clean water, waste management and sanitation, and economic and workforce development by leading the way in addressing one of the most hazardous forms of plastic waste: single-use diapers. These diapers pollute rivers a vital water sources, and overwhelm landfills. Through the locally made, high-quality Reusable Diaper Initiative, the city is pioneering a sustainable solution that protects water sources and the environment while creating local jobs.

Surabaya (June 25, 2025) – Eri Cahyadi today announced that Surabaya has been selected as one of the 50 a finalists of Bloomberg Philanthropies’ sixth Mayors Challenge, a competition to spur local government innovation that improves lives in cities around the world. The sixth Challenge elevates municipalities that have proposed the boldest ideas to bolster essential municipal services. The 50 finalists, selected from more than 630 applications, together hail from 33 countries and represent over 80 million residents.

Surabaya will receive $50,000 to prototype their idea, which introduces a locally made, reusable diaper system to tackle one of the city’s most urgent environmental threats: single-use diaper waste. Due to their complex multi-layer materials, odor, lack of reuse value, and contamination with pathogens, these diapers pollute the Brantas River — Surabaya’s main water source — endanger public health, and overwhelm landfills. Deep-rooted cultural beliefs and the lack of affordable alternatives make behavior change especially challenging.

The Reusable Diaper Initiative offers a sustainable and culturally sensitive solution, empowering women and marginalized groups to produce reusable diapers, reducing costs for low-income families, lowering rates of rashes and urinary infections, and mobilizing health workers as trusted community influencers to drive behavior change.

City officials will also participate in Bloomberg Philanthropies’ Ideas Camp in July to hone and test their concepts with feedback from experts and fellow peers. In January 2026, the 25 city halls with the most promising ideas will each be awarded $1 million and operational assistance to bring their proposals to life.

“This initiative is not just about diapers—it’s about protecting our rivers, improving public health, and creating jobs for those who need them most, Surabaya is proud to lead with a solution that is locally made, culturally grounded, and environmentally sustainable. Our rivers are vital resources; we rely on them every day, so we must keep them clean and free from harmful waste like used diapers that threaten water quality. We aim to prove that meaningful change can begin with our youngest generation—and spark a movement that reaches across the nation and beyond.” said Mayor Eri Cahyadi.

The 630 ideas submitted to the Mayors Challenge reflect some of the greatest public service challenges facing cities today—as well as the creativity that animates local governments across the globe. A third of U.S. and Canada applicants, for example, devised solutions addressing housing and shelter. Nearly half of the applicants from Africa proposed upgrades to waste collection and management. One out of five applicants from the Asia-Pacific region focused on cleaner water, air, and infrastructure, and 22 percent of European applicants sought ways to reduce poverty or enhance social inclusion.

The 50 finalist ideas were selected for their originality, potential for impact, and credible vision for delivery.

Surabaya’s initiative reimagines waste and sanitation services by introducing a reusable diaper system that tackles non-recyclable waste at its source. By ensuring access to high-quality cloth diapers and integrating local production, health education, and behavior change into public service delivery, the city transforms a major environmental threat into a catalyst for improved public health, local job creation, and long-term sustainability.

“Local government is where people meet policy—and where government improves lives and builds trust,” said James Anderson, who leads the Government Innovation program at Bloomberg Philanthropies. “That’s why municipal innovation isn’t about grand gestures—it’s about solving hard problems under pressure, often with imperfect tools and finite resources. These Mayors Challenge finalists stand out because they’re not just thinking creatively—they’re designing solutions that reckon with the complexity of implementation and the urgency of their residents’ needs. Their proposals reflect a new standard for public sector achievement: ambitious, yes, but also grounded, disciplined, and ripe for real impact.”

The 50 finalist cities are: Abha, Saudi Arabia; Addis Ababa, Ethiopia; Ansan, South Korea; As-Salt, Jordan; Barcelona, Spain; Beaverton, U.S; Beira, Mozambique; Belfast, United Kingdom; Benin City, Nigeria; Boise, U.S.; Boston, U.S.; Budapest, Hungary; Cap-Haïtien, Haiti; Cape Town, South Africa; Cartagena, Colombia; Cauayan, Philippines; Choma, Zambia; Cuenca, Ecuador; Detroit, U.S.; Fez, Morocco; Fukuoka, Japan; Ghaziabad, India; Ghent, Belgium; Greater Visakhapatnam Municipal Corporation, India; Helsinki, Finland; Honolulu, U.S.; Kanifing, Gambia; Kyiv, Ukraine; Lafayette, U.S.; Lower Hutt, New Zealand; Maceió, Brazil; Marseille, France; Medellín, Colombia; Mexico City, Mexico; Naga, Philippines; Ndola, Zambia; Netanya, Israel; Nouakchott, Mauritania; Pasig, Philippines; Rio de Janeiro, Brazil; San Francisco, U.S.; Seattle, U.S.; Seoul, South Korea; Sialkot, Pakistan; South Bend, U.S.; Surabaya, Indonesia; Taipei, Taiwan; Toronto, Canada; Turku, Finland; and Yonkers, U.S.  

In this round of the Bloomberg Philanthropies Mayors Challenge, more funding will be distributed and more cities will be assisted than in the previous five Challenges which each selected between five to 15 winners.

The new Mayors Challenge builds on more than 10 years of work led by Bloomberg Philanthropies to discover, nurture, and drive innovation in cities. The awards to date across five previous rounds of competition have provided 38 winning cities with funding and technical assistance to realize their ideas for addressing civic issues. By supporting the replication of the most successful winning ideas, Bloomberg Philanthropies has expanded the impact of the Mayors Challenge to 337 other cities globally, reaching over 100 million residents around the world.

When single-use diapers are dumped into the Brantas River, the harmful substances they contain can contaminate both the environment and human health. Unlike other plastic waste, diapers cannot be recycled they pile up in landfills. Reducing diaper waste at the source can ease landfill pressure and allow public waste management funds to be redirected to more critical priorities. said Dedik Irianto, Head of Surabaya’s Environmental Agency.

With the expansion of the Bloomberg Cities Idea Exchange, future Mayors Challenge-winning ideas and other locally led solutions supported by Bloomberg Philanthropies will have new potential to scale—serving as models and catalysts for how governments solve problems across the globe. 

To learn more about the 50 finalist proposals, visit mayorschallenge.bloomberg.org.