A recent six-month pilot program in Metro Manila has demonstrated the potential of autonomous river-cleaning vessels while revealing critical shortcomings in pollution management strategies. The Metropolitan Manila Development Authority (MMDA) tested two AI-powered boats called Clearbots in tributaries of the heavily polluted Pasig River, uncovering both technological promise and systemic challenges.
These electrically powered vessels, developed by Clear Robotics, can operate autonomously or via remote control. Equipped with conveyor mechanisms to collect floating debris and sensors to monitor water quality, the Clearbots are designed specifically for narrow urban waterways like Manila's tributaries and esteros (urban creeks).
Supported by the Asian Development Bank (ADB) through a climate innovation program, the pilot allowed the MMDA to evaluate the technology at minimal government cost while providing the developer with valuable performance data.
The Pasig River represents an ideal—though unfortunate—testing ground for such technology. Despite being only 27 kilometers long, this waterway contributes disproportionately to global ocean plastic pollution, accounting for approximately 6.4% of plastic waste entering oceans from rivers worldwide, or about 63,000 metric tons annually.
During the pilot, one vessel deployed in Pasig City's Ilugin River cleared 138 metric tons of water hyacinth between October 2025 and January 2026—enough vegetation to fill 277 trucks and cover over 7,000 square meters. In San Juan City's San Juan River, another vessel collected 5.3 metric tons of floating waste in just two months, complementing existing cleanup efforts.
However, the experiment exposed fundamental limitations. While the Clearbots proved effective at removing waste, new pollution continuously arrived from upstream sources, particularly in the San Juan River. This highlighted what experts describe as a "revolving door" problem: cleanup efforts downstream are undermined by inadequate waste management upstream.
"Effective river rehabilitation therefore requires a broader set of interventions, including improved upstream waste management and changes in community behavior," concluded the ADB's analysis of the project.
The findings underscore that technological solutions alone cannot solve Manila's water pollution crisis. Despite numerous cleanup initiatives by government agencies, private companies, and communities, pollution persists due to uncoordinated efforts and complex hydrological factors. The Pasig River's tidal nature complicates matters further, causing waste to circulate or accumulate rather than flow downstream.
Experts note that the country already has a legal framework for waste management through the Ecological Solid Waste Management Act, but enforcement remains inconsistent. Technical and material support for local communities to comply with regulations is often inadequate, particularly in densely populated urban areas.
Addressing these systemic issues with a comprehensive, bottom-up approach would not only enhance water pollution control efforts but also improve flood management—a critical concern in Metro Manila's crowded landscape. The Clearbot pilot demonstrates that while innovative technology can be a valuable tool, it must be integrated into broader strategies that address pollution at its source.