What is the concept of non-traditional water source? thank you

A: Traditional water sources generally refer to surface water such as rivers and groundwater. Non-traditional water sources refer to water sources different from traditional surface water supply and underground water supply, including reclaimed water, rainwater and seawater.

Extension:

Rainwater: To develop rainwater resources, in addition to solving domestic water consumption, we should implement water-saving irrigation according to local conditions, so as to store it in autumn and use it in spring, and store it for a long time and use it for a short time, which can not only protect water resources, but also realize sustainable utilization.

Building water: Sewage generated by bathing (except flushing toilets) in residents' lives can meet the requirements of low water quality after simple treatment.

Seawater: Coastal cities can directly use seawater to flush toilets, and seawater desalination can supplement fresh water to ensure the stability of water supply for residents in coastal cities.

In recent years, the utilization rate of non-traditional water sources has become a key indicator of water saving worldwide. According to the arrangement of the Ministry of Housing and Urban-Rural Development, China Institute of Building Research has clearly defined the water quality and application scope of non-traditional water sources.

Municipal tap water and underground well water shall not be used as water sources for residential quarters, street greening and landscape irrigation and spraying, and non-traditional water sources such as rainwater and reclaimed water shall be given priority.

Baidu Encyclopedia-Non-traditional Water Source