Green Plumbing

Answer: B - A purification system is a useful addition to a rainwater harvesting system, but is not necessary for most rainwater reuse purposes such as landscape irrigation that can work well with untreated rainwater. A catchment surface (e.g. roof), a conveyance system to move water to storage (e.g., gutters and pipes), and a storage system (e.g., tank or cistern) are all necessary components of any rainwater harvesting system.