Advantus was retained as a subconsultant to analyze storm sewer system and combined sewer system flow meter data for the Pittsburgh Water and Sewer Authority (PWSA) Green Infrastructure flow monitoring program. Quality Assurance / Quality Control (QA/QC) of flow monitor data is critical to the evaluation process. Comparing pre- and post-construction flow data is an important factor in determining the effectiveness of a Green Infrastructure project. QA/QC of the data ensures that the flow monitors are reporting accurate data.

Advantus reviewed flow and rainfall data associated with approximately 120 locations over three separate projects. Advantus engineers downloaded flow monitor data, maintained a spreadsheet for each location, and produced Manning scattergraphs and hydrographs in order to thoroughly perform a QA/QC of the data to ensure monitors were recording accurate readings. Data anomalies pertaining to level, velocity, flow, or pressure readings were documented and reported. Advantus evaluated monitor performance and identified potential issues, such as shifting monitors or debris, and provided a weekly list of monitoring sites that required attention. This weekly report served as a tracking tool for PWSA management who then commission work crews for ongoing sewer system maintenance.

Flow monitor data was also compared to rain gauge data to evaluate response to wet weather events. Additionally, Advantus used the EPA Sanitary Sewer Overflow Analysis and Planning (SSOAP) toolbox to analyze rainfall data for the purpose of determining if flow data from a significant number and intensity of wet weather events was captured. A weekly report was developed and submitted to include monitor uptime, any emerging or noted issues that required attention, associated hydrographs, and project statistics.