Infiltration/Inflow Methodology Using Pump Station Network

To compute flow through a station with a manifolded force main, it is necessary to know, in real-time, specifically which pump was operating against a specific pressure. This type of historical analysis is almost never possible because operating pressures are not known. This was the case at Brevard County, Florida. On the other hand, there was substantial data available in terms of pump station operating hours by day by pump. This data was used in a custom-designed spreadsheet hydraulic model where pump operating points were deduced through an interactive process of balancing flows from tributary pump stations. This methodology yielded results at a fraction of the cost of flow monitoring concurrently with real-time pressure monitoring. The data was used to compute the levels of Infiltration/Inflow (I/I) in the South Beaches regional wastewater collection system. The benefits gained also included a shortening of the overall project time and the ability to estimate flows from a unique, historical rainfall without performing short-term flow monitoring.