The tap water in Cambodia isn’t all that terrible. Distribution, on the other hand, is rather iffy. As a result, it has become popular (for good reason) to treat water at the point of use. Enter – the biosand filters! You can find biosand filters all over Cambodia. I’m not going to go into all the math behind how it works, though I can if you want, but you put dirty water in the top, clean water comes out. Getting these to work is also a matter of education. If you put clean water in, dirty water comes out, for example. Or, if you have impatient children around who don’t want to wait for clean water and try to drink the dirty water off the top. An awful lot about clean water boils down to education. While Ian and I were in Cambodia last fall we went around various Transform Asia sites and tested their biosand filters. I suspect it won’t be the last time we see these bad boys!