Promoting Sustainable Clean Water Access: An Eco-Friendly Rainwater Filtration System Using Coconut Shell-Based Activated Charcoal and Crushed Glass in Water-Scarce Communities

Abstract

Water scarcity and declining water quality continue to affect many communities in the Philippines, particularly in Batangas, where contamination of groundwater and rainwater sources has become a growing concern. This study developed and evaluated an eco-friendly rainwater filtration system utilizing coconut shell–based activated charcoal and crushed recycled glass as sustainable filtration media. Three charcoal-to-glass ratios (3:1, 1:3, and 2:2) were tested to determine their effectiveness in improving rainwater quality, as measured by color clarity, odor removal, and reducing impurities. Using a quantitative experimental research design supported by a community-based survey, the study assessed both the filtration performance and practical applicability of the system. Results demonstrated that the 3:1 ratio consistently produced the best outcomes, showing the clearest water, complete odor removal, and the highest reduction of particles. Comparative analysis further revealed that the proposed system is more cost-efficient, accessible, and environmentally sustainable than conventional commercial filters due to its reliance on low-cost, biodegradable, and locally available materials. Survey responses indicated strong acceptance of the system for household and community use. Overall, the findings suggest that combining coconut shell–based activated charcoal with crushed glass presents a viable, affordable, and sustainable solution for improving rainwater quality in water-scarce communities.

Introduction

The text presents a study on developing and evaluating an eco-friendly rainwater filtration system using coconut shell–based activated charcoal and crushed glass to address water scarcity and contamination in Batangas, Philippines. Although the country has abundant water resources, industrialization, pollution, arsenic contamination, and climate change have reduced access to safe drinking water, particularly in water-scarce communities such as Taal, Batangas.

Rainwater harvesting is identified as a sustainable alternative, but untreated rainwater may contain contaminants and microorganisms, making filtration necessary. The study proposes a low-cost, sustainable filtration system that uses locally available and recyclable materials. Coconut shell–based activated charcoal serves as an effective adsorbent for odor, color, and impurities, while crushed glass functions as a mechanical filter.

The research employed a quantitative experimental design, testing three charcoal-to-glass ratios (3:1, 1:3, and 2:2) to evaluate filtration effectiveness in terms of color clarity, odor removal, and impurity reduction. Residents from water-scarce communities in Taal, Batangas participated as respondents through surveys and system evaluation.

Results showed that the 3:1 ratio (higher charcoal content) was the most effective in improving color clarity, odor removal, and impurity reduction. Overall, the eco-friendly filtration system was found to be more cost-efficient, accessible, and environmentally friendly than commercial filtration systems due to its use of local, low-cost, and sustainable materials.

The study concludes that the proposed filtration system is a practical and sustainable long-term solution for improving rainwater quality and promoting clean water access in water-scarce communities, while also supporting waste recycling and environmental sustainability.

References

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Copyright

Copyright © 2025 Kristelle Jane C. Acedera, Ken Ryzen A. Acosta, Firstephen C Alvarez, Kayesha Valerie C. Andal, Aillz Kimzleht A. Angulo, Ericka Sandra C. Axalan, Aaron Jay C. Coronado, Bryle A. Armeza. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.