Which of the following would be considered a grandfathered water right?

A grandfathered water right refers to water rights that were established under prior legal frameworks or systems before new regulations or laws were put in place. These rights are preserved and allowed to continue under the original terms, despite changes in laws that might limit or restrict water usage.

In this context, the Type II water right is correct because it often represents rights acquired prior to more modern regulations, particularly in Arizona, where water rights systems have evolved over time. These rights are typically associated with specific uses and locations in historical water management practices.

Other options do not fit the definition of a grandfathered water right. An exempt domestic well, while it may also convey certain rights, is generally subject to current regulatory constraints and does not imply the historic legal backing of a more established water right. Flood areas and riparian districts relate more to land use or geographic characteristics rather than representing rights that are preserved under older laws. Thus, Type II water rights serve as a clear example of grandfathered rights under the described framework.