City of Atlanta Department of Watershed Management


Atlanta, GA


Wastewater Engineering

Located in northwest Atlanta along the Chattahoochee River, RM Clayton Water Reclamation Center (WRC) was experiencing chronic grit-removal issues that required urgent upgrades to its headworks facility, which serves as the plant’s first line of defense in wastewater treatment. As part of the BGR2 joint venture team, Gresham Smith identified inefficiencies in the facility’s existing grit removal and screening system, recommending a new technology solution that helped one of the largest water treatment plants in the southeastern United States optimize downstream treatment and improve long-term compliance.

mgd peak-instantaneous flow
grit removal
Exterior image of RM Clayton WRC’s headworks facility.

Getting to the Root Cause

To solve RM Clayton’s grit-removal puzzle, we began putting the pieces together with a root-cause analysis of the headworks. We also applied our problem-solving skills to a grit characterization study, a technology evaluation for new screening and grit removal systems, and a business-case evaluation and conceptual design that included sustainability, climate adaptation and resiliency improvements to expand the rated capacity of the facility to 320 million gallons per day.

Multi-tray grit-removal units at RM Clayton WRC’s headworks facility.

Saying Goodbye to the Nitty-Gritty

Our recommended solution consisted of new multi-rake screens as well as multi-tray grit-removal units optimized for wet weather and combined sewer peak-flow events. To expedite construction, we led the development of a design-build procurement package and served as the owner’s engineer for the $54 million project.

Large, white cylindrical structure with pipes at RM Clayton WRC’s headworks facility.

An Award-Winning Solution

Advancing resiliency while improving operations and maintenance costs, the project represents one of the largest multi-tray grit-removal installations in the world. RM Clayton’s headworks can now handle up to 320 mgd of peak-instantaneous flow, providing the facility with 95 percent grit removal. The project was recognized by the South Atlantic Chapter of the Construction Management Association of America (CMAA) with an achievement award in the Public Works category.