. >> wertheimer also managed to persuade the well-known argentinian tv presenter julian weich to supportthe project. >> there's a major problem with clean drinking water in argentina, and indeed, across the world. nicolas is addressing this issue not justst because he's a doctr but because he wants to solve a problem. i trust him. i believe in him. we're supporting each other in a bid to find a solution. >> a few hundred families live along this part of the river. it can only be reached by water. wertheimer spends a lot of time on the phone sorting things out. today he's accompanying some local children to school. julian and nicolas founded the proyecto agua segura initiative in late 2015. they see themselves as social entrepeneuers. children's health is one of their first priorities. their digestive systems are more vulnerable than adults'. they have lower immunity to parasites in contaminated water. at school, the children get breakfast and lunch. and now, clean water, too. >> i'm very pleased. the principal is very committed and always gives us a warm welcome. the device works by itse