E.coli and Coliforms are “Indicators” which means they provide evidence that harmful contaminants are getting into the water. E.coli (0157) can, and does seriously harm people, however other viruses are just as lethal e.g. Cryptosporidium. A failed water test is a clear indicator that you need to do something about your drinking water and that there is a risk to public health – that is why the Environmental Health Department will have sent you a letter, suggesting you take steps to make improvements.

New Private Water Supply Regulations – pdf »
– what do they mean for owners and consumers?