B&N designed an expansion of the Bob McEwen Water Treatment Plant (WTP) in Clermont County, Ohio to better serve more than 100,000 area residents. The $12.4 million expansion project increased capacity from 10 mgd to 20 mgd. The project also included improvements to the plant’s treatment processes to help reduce disinfection byproducts (DBPs) and treat manganese present in the surface water that impacts the water’s color and taste.
The Bob McEwen WTP treats surface water from a local reservoir. The water from the reservoir is challenging to treat because it has characteristics of both surface water and groundwater. By the end of the summer months, the reservoir runs out of oxygen, allowing manganese in the soil to become mobile and the water takes on groundwater characteristics.
Extensive testing was conducted to identify the right chemical treatment regime and filtering process to treat the water. The solution includes an initial chemical treatment that removes the solids and organics found in surface water. Next, chemicals and filters remove the manganese and remaining small particles. New granular activated carbon (GAC) contactors were built to remove any remaining organic compounds or DBPs.
The plant expansion also included an additional flocculation/sedimentation tank and a new building for the GAC contactors.