Currently I am working with norovirus. There are not much data available in water quality regulations about norovirus limits. Therefore if it is possible to consider the risk from norovirus, it also can be helpful as I think.
You could also check out the Canadian Water Quality Index and its related publications. You can find them on the CCME website at www.ccme.ca, and search there for the WQI
Ground water quality is for irrigation or drinking, it means if you classify in saline or RSC which is using for irrigation purpose. if you you want to classify on the basis of drinking, then criteria of water quality may different