While finding clean water to support the population of Sub-Saharan Africa is an ongoing problem, in 2006 Ibelatha Mhelela, the principal at a primary school in Tanzania, implemented a simple solution.

Turns out, even if people live nowhere near a clean source of water, as long as they have plastic bottles they can CREATE clean water. It’s known as the SODIS program. Basically, you peel the label off any plastic water bottle and fill it with standing water, as long as the water isn’t completely brown. Then place the bottle on top of a metal surface (for better heat conductivity) and leave it alone. Within six hours, the UVA radiation will kill parasites, bacteria and other harmful elements in the water, making it safe to drink.