Getting the Most from Your Flow Monitoring Program – Improving Data Reliability

Flow monitoring is a critical step in analyzing a sanitary sewer system, whether it is for sanitary sewer evaluation surveys (SSES), calibrating hydraulic models or sizing system upgrades. However, given the number of flow meter types and manufacturers available combined with differing system conditions (i.e. depth of flow, velocity, slope, pipe type, etc.), obtaining reliable data is difficult if the correct techniques are not utilized. To compound this problem, the introduction of CMOM-related language in recent consent orders is dictating strict reliability requirements with the consequence of continued metering if requirements are not met. As such, if reliable flow monitoring data is not collected, costs associated with metering projects can increase substantially. Flow monitoring provides valuable data for evaluating a sewer system. When performed properly, flow monitoring is an excellent diagnostics tool that can be used to accurately identify system flow constituents (including extraneous flows), to identify areas in need of improvement and thus improve system reliability and reduce sanitary sewer overflows. Through proper site evaluation, meter installation, calibration and routine maintenance, data reliability is improved and program costs are reduced. Source: WEFTEC 2009 Proceedings