Tarlton is General Contractor for this 30-month project to increase the capacity of the St. Louis Metropolitan Sewer District's Lemay Wastewater Treatment Plant and enhance plant operations under a wide variety of operating conditions including heavy storm surges.
When completed, about 20,000 cubic yards of concrete will have been poured at the site. Improvements include two grit basins with channel grinders, a primary sludge pump station, a grit handling building and four primary clarifiers. The work involved deep excavation, a tunnel over 500 feet long, installation of 12-foot-diameter storm and sewer piping, and numerous large cast-in-place underground vaults/junction chambers. The project also entails associated piping, valves, yard structures, electrical components and instrumentation, as well as other related work.
In addition, the team successfully completed a temporary bypass to tie into a 96-inch influent pipe -- believed to be only the second time in the United States this operation has been completed on a pipe with a diameter this large.