Appropriate technologies in the field
Many people ask us about the technology or the “hardware” in the field. To some it’s the most important part of what development organizations do in the field.
To us, what is important is that it lasts. And that’s not only dependent on the hardware—that’s a software problem.
Technology is the vehicle to get a long-lasting solution. Most times what’s more important than the type of pump or the style of latrine is whether there is a system set up to maintain and operate the system. Can you get spare parts? Who is trained to fix it? Is the community contributing money to the operation? Who’s testing the quality of the water?
You can see that technology is only one small part of the outcome. So while we acknowledge that the technology is there, it must meet local standards and be chosen by the community—not forced on them.
As you read about the technology on the ground—think about all the other things that happen to make it last.
Traditional Pit Latrine—A pit in the ground with no squatting slab, platform or seat; pit is generally unlined superstructure: walls, but generally no roof or door.
Improved Pit Latrine—A pit in the ground with squatting slab, platform, or seat; pit may or may not be lined, but squat hole and floor are lined with clay/plaster/mortar/cement. Superstructure: walls, roof, and door.
Ventilated Improved Pit Latrine—A pit in the ground with squatting slab, platform, or seat (may also be elevated); pit generally lined; ventilation tube that accesses pit and extends above latrine roof; gauze netting covers top of ventilation tube to trap flies. Superstructure: walls, roof, door and ventilation tube.
Arbor Loo—Shallow pit (0.75–1 m deep) in the ground with removable cement squatting slab; pit unlined; ash and dirt added to pit to help excreta compost; filled in a couple of months and slab removed; tree planted on top of pit and slab placed on new pit. Superstructure: for small children, no superstructure; for adults, semipermanent structure with walls and roof that can easily be moved to next pit (often made of wood). More info
Fossa Alterna (Eco-SAN) —Two shallow (1 m deep), partially lined pits; a removable cement squatting slab that is placed over pit in use and once pit is full, moved to cover other pit; filled pit is covered and composts while other is in use; once pit is composted (6-9months), compost is emptied and pit can be used again. Superstructure: roof, walls, doors. Read a short case study and read about how fossa alterna (Eco-SAN) is creating business opportunities.
Urine Diversion (Skyloo)—Elevated above the ground with two vaults; squatting slab, platform, or seat with two chambers—one for urine and one for feces; doors in back to remove compost from vault; urine piped out into storage tank. Superstructure: roof, walls, and door.
Pour Flush—A pit in the ground with squatting slab, platform, or seat; pit generally lined; a water-sealed pan with a U-shaped pipe below the slab, which goes into pit; 1-3L of water poured by hand for flushing. Superstructure: roof, walls, and door.
Flush Toilet—A seat above a cement platform; uses cistern or holding tank for flushing water and excreta; a water-sealed pan with a U-shaped pipe below the seat, which goes into either a pit, septic tank, or piped sewer system. Superstructure: roof, walls, and door.
A Few Selected Water Technologies
Afridev—Part of a family of pumps that originated in India (Mark II and III) that is the darling of the sector. The Afridev and its sisters are really the first Village Level Operation and Maintenance (VLOM) hand pumps that moved beyond isolated production and extended beyond the original country (India). VLOM is simple and can easily be repaired by a local mechanic so it can be managed at the village level without lots of backup (theory by which these pumps were made). Afridevs are everywhere (Mark II and III are rarer now). It’s fairly robust and should last 14 years if well maintained.
Rope Pump—Developed first in Nicaragua and widespread there. Spread slowly to other countries thanks to much innovation. The principles of the Rope Pump are simple, a rope with pistons one meter apart that goes down the well/borehole, and finds what is sometimes called a transformer box at the bottom, which is basically a block of concrete with something simple (like a beer bottle—Zambezi the best transitioner for rope pumps in Mozambique) that the rope goes around and into a series of PVC pipes back up to the outlet valve. Water is captured in the box at the bottom of the well/borehole, grabbed by the piston on the rope, and run up the PVC and out. The pumping part is basically a wheel with an inside-out tire over it that a person turns in a circle (so the rope moves easily and is not destroyed by contact with metal), and the rope goes around and around and water flows.