The purpose of this presentation is to provide a project overview and challenges for an underground linear equalization basin and conveyance upgrade for the City of Memphis. The focused project consists of a 1 MG equalization basin located in the Fletcher Creek Basin located in the eastern part of Memphis, TN. This basin will increase the wastewater system capacity and reduce the likelihood of sanitary sewer overflows in the basin. The initial design consisted of an above ground 1 MG prestressed concrete basin with an 8 MGD pump and corresponding electrical and site support. However, the proposed site presents a unique opportunity to support an underground linear 1 MG storage basin that is gravity supplied and drained. The storage basin would be supplied and drained to separate gravity sewer trunk lines, allowing the elevation difference to achieve an all-gravity system. The project also includes replacing the existing 24-inch conveyance line with a new 42-inch conveyance line by 3,000 LF of open cutting and 450 LF of FRP jack and boring. The project consists of numerous design and construction challenges. The storage basin was designed to be gravity supplied and drained, eliminating the construction and maintenance cost of a pump station, electrical equipment, and related appurtenances. However, with the upstream and downstream sewer systems to remain and the local terrain flatness this made designing the storage basin a challenge. The underground storage basin water height was constrained to 7.25 feet. This promoted challenges to keep the layout within the proposed property, out of the Fletcher Creek stream buffer, out of wetlands, away from existing drainage features, and remaining outside of wooded areas as much as possible. Maintenance was also considered during design. Multiple access points and site water were added. The conveyance portion also presented multiple challenges. The largest challenge was designing the alignment through a water, gas, and electrical utility site. This site contains four gas transcontinental gas main (26”, 26”, 30”, and 36”), local utility gas mains (18”), underground electrical vaults and duct banks, above ground electrical transmission lines, and local water lines and booster station. The new 42” conveyance line had to be designed to pass under all existing utilities. Jack and boring was chosen to mitigate the conflicts, however close coordination with all utility entities is required to ensure minimum disturbances. The new 42” conveyance also had to cross Fletcher Creek. This promoted additional challenges as the new conveyance line had to be installed with low slope to meet existing downstream invert elevations. Close coordination with TDEC was required during design to achieve a successful creek crossing.