Matías Hernández River, Panama

Project lead: Marea Verde


The Matías Hernández River watershed covers 2,062 ha and a length of 28 km in and around Panama City, Panama. The river flows through mudflats and mangroves that are critically important ecosystems that provide protection for coastal communities, support incredible amounts of biodiversity, buoy local fishing and ecotourism industries, and even sequester carbon. Panama Bay is an important and critical ecosystem for biodiversity and related socioeconomic activities including fishing and ecotourism. Every year, nearly 1000 humpback whales visit the protected Panama Bay to nurse their young, and it is a critical stopover site for more than 20 species of migratory shorebirds and as many as two million individuals.

The Matías Hernández River is one of the seven rivers in Panama City that discharge 102,299 t of land-generated marine debris annually into Panama Bay. Nearly 90% of the Matías Hernández River watershed is residential or commercial and supports a population of 356,000, mostly in low-income communities. The mangroves act as a natural barrier, trapping the litter and causing the water to stagnate which reduces the health of the ecosystem and threatens the survival of all that depends on it.

Intervention Plan

Marea Verde will adapt and install a Trash Wheel, based on the water wheel-powered Trash Wheels in Baltimore, Maryland, US. The system aims to prevent plastic from entering the Panama Bay via the Matías Hernández River. The mouths of the rivers leading into Panama Bay form deltas with mudflats making it difficult to access the rivers at low tide. Therefore, transferring the debris directly onto shore at the capture site is the most appropriate approach for this location. The adapted design incorporates a transverse conveyor system, continuously removing the debris to the riverbank. A water wheel provides mechanical power for the conveyor from the river current and solar-powered pumps.

Since 2017, Marea Verde has worked successfully with lawmakers on a law that incorporates recyclable materials, including plastics, in asphalt mix in lieu of a percentage of gravel. Other potential uses for the river plastics include pyrolysis to create energy using cement plant chimneys, generation of biofuels through gasification, and conversion of garbage to inert materials that can be used for construction bricks.

Marea Verde plastic clean up

Community Engagement

Marea Verde is focusing on creating awareness about the Trash Wheel and reducing waste in the Matías Hernández River watershed, using a three-pronged approach: 

  1. Local community engagement through focus groups, workshops, and seed capital to community leaders for pilot recycling projects.
  2. Collaborations with strategic partners to increase media impact, including events, use of traditional and social media (Instagram, live stream), exhibits, artworks made of plastic, and a children’s book to be distributed in the Matías Hernández River watershed schools at no cost.
  3. Engagement with government representatives to identify key policy areas in Panama that should be targeted to improve the plastic and waste disposal problem. These actions include providing data and advocating for the enactment of new policies.

The Team

marea verde logoMarea Verde is a non-profit organization formed in 2017 that focuses on creating awareness and taking action on mitigating pollution from solid waste in the rivers and coasts of Panama. They have developed clean-up initiatives in the Matías Hernández River, and have implemented education campaigns with local schools and awareness campaigns for sustainable alternatives for solid waste management. Marea Verde has also intervened in the clean up and restoration of the mangrove area in Costa del Este with the BoB (Barrera o Basura) low-cost capture system. Redoxigen (Wisy Inc.) is a US-Panama-based initiative that consists of a digital platform that uses computer vision to recognize images and text, and integrates AI, mobile technologies and behavioral design to facilitate efficient operational management. With the support of Carnegie Mellon University, they are using AI to categorize plastic trash as it moves along the conveyors. Clearwater Mills is a sustainable environmental technologies company based in Baltimore, Maryland, US, and will help with engineering the Trash Wheel.

Marea Verde team photo


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