What are harmful affect of lack of clean water on personal health?

The answer depends on whether or not you decide to drink nonpoteable (unclean) or omit water altogether. These are both bad ideas. Nonpoteable water can carry a variety of chemicals and environment pollutant that are harmful for any organism. Just as well this water can also be packed full of nasty diseases like Cholera and Dysentery.

Since the body is composed 75% by water, water is also far too important to not drink. When you don't drink the sufficient amount of water you can eventually become dehydrated and suffer organ failures do tell the lack of water. Here is an interesting fact... Urine can be drunk three times to help keep up water intake if you are stranded without water, though drinking it a fourth time will poison you as the urine has become ammonia.