DEVELOPMENT OF HYDRAULIC SIMULATION MODELING FOR THE SHANGHAI SEWERAGE PROJECT

In the Second Shanghai Sewerage Project, a large-scale sewage conveyance system was constructed to transport the municipal wastewater collected from the city's central areas over 40 km (25 miles) to a pre-treatment plant east of Shanghai. This system has a total service area of approximately 272 km2 (105 mile2) and a service population of more than 3.6 million. Chiang, Patel & Yerby, Inc. (CP&Y), developed a hydraulic simulation model as the application software for the project. The InfoWorks™ CS hydraulic modeling software by Wallingford Software, Inc. (WSI) was used as the platform to establish the hydraulic model. Four major steps were involved in the complete model development. First, a working hydraulic network was setup with available data and proper assumptions. This network includes all key elements of the sewage conveyance system. Three main lift stations were modeled for multiple-pump operation using actual pump curves with wet well level control. A state-of-the-art real-time control (RTC) module was also developed to simulate operation of variable speed pumps. Second, this working model was then hydraulically calibrated segment-by-segment using actual system operating data. After calibration, the predicted water depths closely match the observed values in all data periods selected for model calibration. Third, the calibrated model was further verified in dynamic simulations by comparing simulation results with actual operating data. The verification results indicate that the model simulates the actual system operation quite well. Finally, a comprehensive training program was provided to the operators. Observations in this project prove that the calibrated model can properly predict the operation for this large-scale sewage conveyance system. Based on the complete engineering services provided by CP&Y, the owner's operators are now able to use this powerful tool for developing their control strategies for operation optimization and preparing alternatives for future system expansion.