What defines a non-community water system?

A non-community water system is characterized as a public water system that does not serve a resident population year-round, which is precisely what option B states. Non-community water systems typically serve transient users or non-residential facilities such as parks, restaurants, or schools that only have regular, temporary patrons rather than a permanent community.

Other options do not accurately describe a non-community water system. For instance, a system used solely for agricultural purposes does not qualify as a public water system. Similarly, a system that provides water only to a single household does not fit under the definition of a public water system, and a community water system with under 15 connections is still categorized as a community water system, not a non-community one. Thus, option B accurately encapsulates the criteria that define a non-community water system.