Portable Dam Helped Utility Function During Construction

摘要

The Charlotte-Mecklenburg Utility Dept. (CMUD) in North Carolina required major modifications to an existing chlorine contact basin. Construction required installation of a new concrete contact tank in an active effluent flow lagoon. Designers from HDR created a temporary cofferdam system from Portadam that allowed work to take place in the active basin. Construction of the replacement tank could then occur while the diverted water continued to be processed through the existing lagoon. "Our system does not disturb the subsurface and can perform in flowing waters. This was key to the success of this project," says Tim McTigue, director of business development with Portadam. Once installed, the new contact tank was placed into service, the remaining flow lagoon was drained, sludge was removed and extensive grading was completed. The lagoon bottom and its sloped sides were lined with 10 in. of reinforced concrete, thus converting the remaining 8-acre lagoon into a new flow-equalization cell. The $7.2-million project was completed in 14 months.