This is true because certain manufacturing companies and other industries still donot comply with the governmental regulations and release the toxic wastes containing sulfates, into the water bodies. This contaminates them and the maximum allowed sulfate level of the water body exceeds its limit.
Hey:)
Bottled water is definitely not a long-term plan.
Reducing the water consumption does not really solve the problem.
Store the rain water is a nice choice, but you cannot drink the rain water directly, it needs to be filtered.
Since the contamination is only caused by N and P, it should be easy to filter out, but still, it depends on the type of the compound of N and P.
I would choose the last option.