What Are These Black Balls Doing in the Reservoir?

In Los Angeles, a remarkable sight unfolds as a truck releases countless black balls into a sprawling water reservoir. At first glance, it might seem like an attempt to create the world's largest ball pit, but this spectacle serves a far more critical purpose – ensuring the safety of the city's drinking water supply. These black spheres play a crucial role in preventing the formation of a carcinogenic element called Bromate in the water. The story behind these shade balls begins with Bromide, a harmless substance formed in water from salt. Typically, chlorine is used to disinfect water without any adverse effects. However, introducing Ozone for disinfection led to an unintended chemical reaction, transforming Bromide into harmful Bromate. This discovery prompted officials to take imme ...