It should be noted that much ...

It should be noted that much of contaminated water sources in India are a result of lack of sanitation. We must put some effort into preventative measures, not just solutions to treat the problems. Everyone would love an "affordable cheap method" to purify water, but the word purify is subjective. Water quality in India can be improved through increased use and building of proper sanitation facilities that reroute excrement away from drinking water sources.