@Valadian i see your point.But theres a disease named cholera it spreads from not purified water sources.They main symptoms are diarrhea and vomiting can lead to rapid dehydration and death in some cases.We can all see the piles of trash and dead body so theres always a chance to contamination of water source from bacteria or chemical pollution. In game mechanics let the water from pumps and ponds to be 10% chance to be tainted.And for some time of sickens theres like 1% chance that you end dead. Anyway we can always boil the water or use bleach or purification tablets as for the water filtration system posted by Combine actually they not that common in post soviet rural country.
