It is here that the water is mixed to make sure the added chemicals are well blended and react with all of the smaller particles. This is called sedimentation. Following this is the filtration system. The water is drawn through filters, which remove finer particles still in the water for additional purification. In the final treatment fluoride is added to help prevent tooth decay, while zinc orthophosphate is added to minimize corrosion activity between water and piping materials.
Ammonia is added to reduce chlorine-like tastes and to maintain the chlorine in the water.
After all these processes are completed, the water is then distributed. Baxter serves the eastern half of the city, bounded to the west and north by the Schuylkill River, Roberts Avenue and Tabor Road and to the east by the city limits. From Harwell Lane east, the Baxter and the Queen Lane Treatment Plants jointly serve Chestnut Hill. When the Baxter Plant was opened in 1909 it was called the Torresdale Plant. It was renamed in 1982 for Samuel S. Baxter, the first Philadelphia Water Commissioner.