Any time a new service is added to a Public Water System

When there is plumbing work that requires a permit and involves a major modification (i.e., a material improvement, correction, or addition) to the private water distribution system. The “private water system” refers to the facilities on the owner’s side of the meter.

When certain household modifications are being made that do not require a permit but that nevertheless require a customer service inspection. Examples of these kinds of modifications include the remodeling or expansion of plumbing or water-using devices, a customer request for the installation of a larger meter, the drilling of a private well, or the installation of a rainwater harvesting system 

When the water supplier believes that a cross-connection or other potential contamination hazard exists. In such a case, the water supplier must provide written justification to the customer for requiring an inspection by specifically identifying the threat that is believed to exist.