Abstract Submission: The Scott Candler Water Treatment Plant (SCWTP) stores drinking water for DeKalb County, Georgia, in three reservoirs: Reservoirs 1 and 2 sit on the east side of Winters Chapel Road in DeKalb County, whereas Reservoir 3 is located on the west side of Winters Chapel Road in Gwinnett County, though all are managed by DeKalb County. Inflow from the Chattahoochee River is directed into a flow splitter box located on the north side of Reservoirs 1 and 2, where it is divided and channeled into the three reservoirs. Water transfer between the reservoirs is limited to an elevation-controlled overflow structure between Reservoir 1 and Reservoir 2. The reservoirs are located in a heavily populated area, and therefore required an updated dam breach model. DeKalb County Utilities retained Arcadis to model various dam breach scenarios for each of the reservoirs, as well as to update the Emergency Action Plan. The dam breach analysis utilized HEC-RAS 2D modeling, using the Shallow Water Equations and Eulerian-Lagrangian computation method. A total of seven dam breach scenarios were run, all using a sunny day-esque mode of piping failure. This presentation would focus on the worst-case scenario of the simultaneous breach of Reservoirs 1 and 2, which has the capacity to flood thousands of residential homes within minutes.
.jpg "Amy R. Doneff, EIT (she/her/hers) photo")
