Village of Indian Hill’s Water Supply Treatment Process

Source: Indian Hill Village Bulletin dated May 2, 2008

Indian Hill’s water comes from the Little Miami aquifer located near Milford and Camp Dennison. Indian Hill has nine wells. Each well has a depth range of 35 to 75 feet and produces water at a rate of 300 to 700 gallons per minute.

Once the water is pumped from the well field to the treatment plant located on State Route 126 in Camp Dennison, it enters one of the 12 ion exchange water softeners. These softeners reduce the water hardness from 300-400 mg/L to 110-180 mg/L. During the softening process, the calcium and magnesium ions, which cause hardness in water, are replaced with sodium ions. The softeners used in Indian Hill’s water treatment process are similar to those found in homes; however, household water softeners use approximately 150 pounds of salt every few months, and Indian Hill uses 25 tons each week.

After the water is softened, three chemicals are added to the water supply. The first chemical, chlorine, is added for disinfection purposes. Next, fluoride is injected to help prevent tooth decay. Finally, zinc orthophosphate is added to help control corrosion of household piping and plumbing fixtures.

Indian Hill has an EPA certified laboratory to help monitor the treatment process and water quality. The water treatment staff consists of four operators. All of the operators are licensed by the Ohio EPA in water supply, and are certified to perform laboratory testing. The lab has the ability to test water for hardness, chlorides, fluoride, chlorine, pH and total alkalinity. These tests play an important role in monitoring the proper operation of an ion exchange plant, as well as, meeting Ohio EPA water quality regulations.