Plastic pollution in rivers remains one of the most significant pathways by which plastic and other waste enter marine ecosystems. According to several studies and reports by the Chemolex team, more than 157,000 metric tons of plastic waste leak into the Indian Ocean each year via river systems. To combat this, Chemolex has designed, locally fabricated, and installed plastic-capture interceptors along rivers such as the Athi River and its tributaries. These devices trap floating plastic waste, preventing it from reaching the ocean while enabling community-led collection and recycling. Plastic pollution is more than just an environmental nuisance – it represents a rising risk of climate resilience, health, and livelihood challenges and especially for the vulnerable communities living in the riparian section of the rivers. As a company, we are cognizant of the fact that mismanaged plastic harms both the marine and terrestrial ecosystems. In addition, it is just the very poor and most vulnerable who live close to the sources that are mostly affected and predisposed.
Plastic pollution in rivers remains one of the most significant pathways by which plastic and other waste enters marine ecosystems. According to several researches and reports by Chemolex team, more than 157,000 metric tons of plastic waste leak into the Indian Ocean each year via river systems. To combat this, Chemolex has designed, locally fabricated, and installed plastic-capture interceptors along rivers such as the Athi River and its tributaries. These devices trap floating plastic waste, preventing it from reaching the ocean while enabling community-led collection and recycling. Plastic pollution is more than just an environmental nuisance – it represents a rising risk of climate resilience, health and livelihood challenges and especially for the vulnerable communities living in the riparian section of the rivers. As a company we are cognizant of the fact that mismanaged plastic harms both the marine and terrestrial ecosystems. in addition, it is just the very poor and most vulnerable who live close to the sources that are mostly affected and predisposed.
By installing the plastic waste interceptors at strategic points in the riverine system and creating tens of waste collection points in the informal settlements, we directly reduce climate-related risks such as
blocked waterways, and flooding, while improving sanitation and environmental quality.
Some of the Key Outputs of the Plastic Interceptors include:
- installation of 13 plastic interceptors across urban waterways in Nairobi and environs.
- Removal of over 1,600,000 kilograms of waste plastic from four different rivers
- Creation of community waste collection infrastructure integrated with device operation – that feed waste into the recycling streams.
- Creation of direct and indirect employment for the women and youth.
Lessons Learnt and Risks Involved:
– One of the earlier lessons we learnt was that community engagement was very critical – the need for early reconnaissance revealed that selecting sites with active youth/women groups boosted device adoption and security. For example the devices in almost all the areas of operations were run and managed by the resident youth groups.
– River hydrology and Flood Risk must be accounted for in-the construction and installation of the devices. – to be honest, all our devices suffered immeasurable damages or even loss during flood events. As is reported to one of our partners and stakeholders – “Some of the devices were completely swept off by he floodwaters. One evening they are there- and the next morning, there is nothing to see..” To mitigate this challenge we resorted to sturdier metal frames, protective shielding around the motors and flood responsive design enhancements. For some cases, we made mobile interceptors that could easily be pulled away during flood events.
-Vandalism and maintenance – theft and damage of mechanical parts of the interceptors was a common occurrence in the informal settlements. we had to combine different techniques like locking mechanisms, awareness campaigns on the benefits of the devices as well as ownership and community buy-ins. if they felt the machine was theirs and was directly pegged to their income, cases of vandalism drastically reduced.
-Data and Monitoring Needed- while devices physically capture plastic and other floating waste, the real value lies in accurately capturing and measuring or tracking the actual volumes, the types of plastics, and maintenance events. All these factors create a bottleneck for reporting.
– Integration with Downstream Value Chains – the captured plastic means very little to nothing unless there is a route to collection and utilization, its transport to recycling site and finally the sorting. As Chemolex, we have created an elaborate value chain that runs from collection to recycling and to the offset of the final product.
-Need for Behaviour Change & Waste Management Systems – The plastic waste interceptor is merely part of a broader waste-management architecture, and without proper upstream and downstream interventions, its success is not guaranteed.
“By installing these devices at strategic locations, we have ensured that plastic removal from the Nairobi river by the youth is easier and risk-free. This innovation is definitely a game-changer in the circular economy.” – Clifford Okoth, Team Leader, Chemolex.
Next Steps….
- Target to install additional river systems across Kenya and other African countries. Slightly over 100 rivers over the span of 5 years.
- To incorporate sensor/IoT monitoring for real-time data on flows, blockages and maintenance needs.
- Strengthen local capacity for device operations, maintenance and community based monitoring.
- Publish detailed impact metric (volumes removed, diversions to recycling, jobs created among others) and use charts to support funding and replication
The Chemolex Plastic Waste Capture Device project has demonstrated that locally fabricated river interceptors are a practical and scalable solution for reducing plastic pollution in Kenya’s waterways. Key lessons include the importance of community engagement, especially involving youth and women, in maintaining and monitoring the devices; the need for regular maintenance to ensure sustained efficiency; and the critical role of partnerships with local authorities and recyclers for effective waste collection and value addition. While challenges such as flooding, vandalism and inconsistent waste flows were encountered, adaptive designs, training and community ownership proved effective mitigation. overall, the initiative has not only improved river health but also fostered social and economic empowerment through circular waste practices.
