Water & Purification
Clean water projects that need no grid power and no imported cartridges. Every method here has documented field performance — read the safety notes carefully, because water treatment is the one area where a half-built system is worse than none.
Concrete Biosand Water Filter
A household slow-sand filter in a concrete body that removes most pathogens and turbidity with no power, no cartridges and no ongoing cost.
Rooftop Rainwater Harvesting with First-Flush Diverter
Catch and store roof runoff, and throw away the dirty first few litres automatically so what reaches your tank is worth storing.
Silver-Treated Ceramic Pot Water Filter
A fired clay pot filter that removes bacteria and protozoa at roughly two litres an hour, sitting in a covered bucket with a tap.
SODIS Solar Water Disinfection Rack
Clear PET bottles on a black-painted roof rack, using six hours of sun to make biologically safe drinking water at no running cost.
Hand-Dug Well with Concrete Ring Lining
Cast concrete rings on the surface, sink them as you dig, and finish with a sealed apron so the well does not contaminate itself.
Rope-and-Washer Pump
A hand-cranked loop of rope with rubber washers that lifts water up to about 35 metres, built almost entirely from salvage.
Community Slow Sand Filter
A tank of fine sand with a living biological layer on top that treats a household or small community's drinking water continuously, with no chemicals and no power.
Hand-Auger Borehole
Drill a small-diameter well by hand with a rotating auger and extension rods, then case and develop it — reaching cleaner water than an open dug well at a fraction of a rig's cost.
Safe Water Storage Vessel
Convert an ordinary jerrycan or clay pot into a narrow-mouth, tap-fitted, lidded storage vessel so treated water does not get recontaminated by hands and cups.
Gabion Check Dam for Gullies
Stack wire baskets filled with stone across an eroding gully to slow runoff, trap silt and let the channel heal itself into a planted terrace.
Sand Dam on a Seasonal River
Build a reinforced concrete wall across a sandy seasonal riverbed so each flood leaves coarse sand behind — a buried reservoir that holds clean water through the dry season.
Moringa Seed Water Clarification
Crush shelled Moringa oleifera seed into a milky suspension that binds silt and much of the bacterial load in turbid water, dropping it out as sludge in an hour.
Protected Spring Box
Cap a natural spring at its eye with a sealed masonry box and pipe it to a raised tap, so people collect flowing water that never touches the contaminated surface.
Basin Solar Still
Evaporate brackish or dirty water under a sloping glass cover and collect the condensate — slow, but it produces genuinely distilled water from sun alone.
DiagramSplit Bamboo Rainwater Gutter
Turn a thatch or sheet roof into a water source with split bamboo gutters and a downpipe — the cheapest rainwater harvesting there is.
DiagramHousehold Chlorine Dosing Station
A measured-dose bottle and dispenser that makes safe chlorination routine instead of guesswork — the cheapest disease barrier in the water chain.
DiagramFolded Cloth Pre-Filter
Four to eight folds of clean cotton cloth over the collection pot strips out the silt, larvae and copepods that defeat chlorine and clog filters.
Buried Clay Pot (Olla) Irrigation
Bury unglazed clay pots between plants and fill them weekly — water seeps out at root depth on demand, cutting irrigation water by half or more.
DiagramTimber & Stone Tank Stand
A braced stand that lifts a full water tank safely to head height and gives you gravity pressure at the tap without a pump.