DIY Gravel-Sand-Charcoal Biofilter¶

Membranes & Advanced Filtration • Est. CapEx: Low-cost / Locally fabricated

Technical Overview¶

A simple, multi-layer water filtration system using gravel, sand, charcoal, and cloth, designed for emergency or outdoor use. It can be built from readily available materials and reduces sediment, some chemicals, and improves taste and odor.

Key Specifications & Engineering Parameters¶

Parameter	Specification
Category	Membranes & Advanced Filtration
Capital Cost	Low-cost / Locally fabricated
Primary Mechanism	Water passes through successive layers: gravel traps large debris, sand captures finer particles, and activated charcoal adsorbs organic compounds, some chemicals, and odors via its porous structure. A cloth layer at the bottom prevents material loss.
Target Scale	Household / Village Cluster
Standard Lifespan	10 - 20 Years

Engineering Trade-Offs¶

✅ Advantages⚠️ Limitations

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Cross-Reference & Interactive Tools¶

Need to evaluate this technology for your specific field site? Run the WhatWater.info Selector Engine to compare it against 100+ alternative solutions.