It's natural for water to carry some bacteria and chemicals. After all, the water we drink, use around the house and bathe in is constantly being recycled between land, sky, sea and home. It's treated and filtered of many toxins each time - but when water management practises slip, contaminated water can make us unwell.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/uk-water-quality-part-2-water-pollution