Developing a Focused and Efficient Calibration Approach for Collection System Models

Calibration of dynamic collection system models involves adjusting model attributes within reasonable ranges to obtain simulated results that closely replicate observed data. Calibration provides the evidence that model simulation results are credible and reliable, building confidence in subsequent use of the model for identifying system deficiencies and sizing appropriate improvements. While the purpose of calibration is clearly understood, approaches for achieving adequate calibration vary considerably because of the unique nature of sewer systems. To avoid unnecessary refinements, a focused and efficient calibration approach is essential. This paper provides guidance for utilities in developing these system-specific calibration approaches for collection system models through review of six case studies based on modeling objectives; level of model detail; monitoring data; calibration approach and results; and validation approaches and results.