Why must water be dechlorinated before draining it from the tank?

Dechlorination of water before it is drained from the tank is essential primarily to prevent harm to local aquatic life. Chlorine is a potent disinfectant used in water treatment to eliminate harmful microorganisms; however, it is also toxic to many forms of aquatic life, such as fish and invertebrates. When chlorinated water is released into natural water bodies, the high concentration of chlorine can lead to detrimental effects on these organisms, potentially killing them or disrupting their reproductive systems.

By dechlorinating the water prior to discharge, the concentrations of chlorine are reduced to levels that are safe for aquatic ecosystems. This practice not only helps protect wildlife but also supports overall environmental health and maintains biodiversity in local water habitats.