What effect do soft waters with a pH of less than 7 generally have on lead and copper?

Soft waters with a pH of less than 7 are generally considered corrosive, especially towards metals such as lead and copper. This is due to the reduced ability of soft water to precipitate minerals and its lower alkalinity. When the pH is less than 7, the water is more acidic, which increases its aggressiveness toward metal surfaces. In such conditions, lead and copper can dissolve into the water, leading to contamination of drinking water supplies.

The corrosive nature of low pH soft water is a significant concern in water distribution systems, where old lead pipes or copper fittings may release these metals due to the acidic conditions. Ensuring the water is pH balanced and treating it to reduce corrosivity are essential steps in protecting water quality and public health.