These compounding effects highlight the urgent need to take stronger action against river pollution and protect the resources that millions rely on.

Southeast Asia must tackle river pollution through a combination of nature-based and policy-driven approaches, supported by effective financing mechanisms.

Nature-based solutions, such as constructing wetlands and reforesting mangroves, leverage the natural purifying functions of ecosystems. These methods not only filter pollutants but also restore biodiversity and strengthen ecological resilience. While Southeast Asia has only begun to adopt wetlands for pollution control, momentum is building. For example, Indonesia launched a nationwide peatland restoration initiative to rehabilitate 2.6 million hectares of degraded peatlands. In Thailand, the King's Royally Initiated Laem Phak Bia Environmental Research and Development Project increased dissolved oxygen levels by 32% and reduced phosphate levels by 88% at its mangrove forest site. These results demonstrate how NBS can enhance the performance of manmade wastewater treatment systems.

Policy measures also play an important role in shaping behaviors and reducing pollution. Instruments like pollution taxes and extended producer responsibility shift the burden of waste management to polluters, encouraging more sustainable practices. Viet Nam has led the way by piloting the Payments for Forest Environmental Services scheme, which requires water supply, hydropower, and tourism companies to pay fixed rates to forest conservation service providers. These providers protect watersheds and preserve landscape aesthetics. However, policymakers still face challenges in measuring impact and conducting accurate economic valuations. To succeed, they must design water pollution taxes that precisely target pollution sources and establish transparent frameworks for calculating, collecting, and allocating revenues.

Institutional coordination is essential to implement these policies effectively. Governments must cooperate across national and local levels to ensure enforcement and accountability. The Mekong River Commission (MRC) exemplifies this approach. As a leading intergovernmental organization, the MRC produces critical data and promotes basin-wide cooperation to support sustainable development. Still, implementation gaps remain especially in linking upstream development projects to incentive or penalty mechanisms based on environmental impact indicators.

Financing underpins all these efforts. Governments traditionally rely on public budgets, international aid, and development loans. However, new and innovative financing mechanisms are emerging. Raising awareness and understanding of tools like blue bonds and blended finance will unlock additional funding sources, which are crucial to combat river pollution in Southeast Asia.

Innovative Financing for Cleaner Rivers in Southeast Asia