What is a cistern used for in plumbing?

A cistern is primarily used for the storage of rainwater, making it a tank specifically designed for rainwater collection. In many plumbing systems, cisterns play a crucial role in capturing and storing excess rainwater, which can then be utilized for various purposes, such as irrigation, toilet flushing, or sometimes even treated for potable use. The ability to collect rainwater helps in water conservation and reduces dependency on municipal water supplies.

While there are other types of tanks in plumbing, such as those for storing hot water, or systems dealing with wastewater filtration, these functionalities do not align with the definition and primary use of a cistern. This distinction is important to understand for effective plumbing design and implementation, especially in areas where rainwater harvesting is both viable and environmentally beneficial.