Water technologies are incredibly diverse and often used in various combinations. Here are a couple of my favorites:
Boreholes w/ Handpumps: When people think of the global water crisis, the lowly well and hand pump is what most often comes to mind. Done right, they provide safe water, are relatively simple to repair, and can easily serve 500 to 750 people. Done poorly, they can become contaminated or fall into permanent disrepair. A 2007 UNICEF study found 124,000 broken hand pumps in Sub-Saharan Africa. It pays to do it right the first time.
Biosand Filters: while there’s nothing fancy about a sand filter, biosand filters add another dimension—a biological layer that consumes pathogens as they pass through the layer. This layer occurs naturally due to the engineering of the filter and removal rates of 98% can be easily achieved. While fairly bombproof and inexpensive, the filter has to be constructed to tight specifications and used correctly, in order maximize effectiveness.
Hydraulic Rams: a little-known technology that dates back to the 1700s, the hydraulic ram pumps water uphill using mechanical force—no electricity needed! Well made hydraulic rams have been known to run for over 100 years without maintenance. For rural communities that have to walk down steep terrain to collect water from a stream or spring, this technology is perfect. Since most surface water is contaminated, this technology has to be treated in order to be safe for drinking.
A quick online search will pull up a long list of technologies. Selecting the right one requires careful analysis of the local context. Success however, depends on much more than the technology itself. Community, local government, and civil society play the most critical roles in generating impact and sustainability. If we want to end the water crisis, empowering local Africans is the surest road to lasting change.