How do chlorides form in out water?

Chlorides in water primarily form through the dissolution of salt compounds, particularly sodium chloride, which can occur from natural sources like seawater intrusion, weathering of rocks, and mineral deposits. Human activities, such as agricultural runoff, industrial discharges, and road salt application, also contribute significantly to chloride levels in freshwater systems. Additionally, chlorides can be introduced through wastewater treatment processes that utilize chlorine for disinfection. These sources collectively increase chloride concentrations in both surface and groundwater.