Slow Sand Filter (SSF)¶

BioSand & Media Filters • Est. CapEx: Low-cost / Locally fabricated

Technical Overview¶

Slow sand filtration is a simple, low-tech biological water treatment system that effectively removes pathogens and suspended solids. It is ideal for small, rural communities with low-turbidity source water.

Key Specifications & Engineering Parameters¶

Parameter	Specification
Category	BioSand & Media Filters
Capital Cost	Low-cost / Locally fabricated
Primary Mechanism	Water percolates slowly through a bed of fine sand (0.15-0.35 mm effective size) at rates of 0.1-0.4 m/h. A biological layer called the schmutzdecke forms on the sand surface, trapping particles and degrading organic matter through microbial activity.
Target Scale	Household / Village Cluster
Standard Lifespan	10 - 20 Years

Engineering Trade-Offs¶

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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.