At this level, you're expected to explain not just what a pump is doing, but why it's operating exactly where it is on its curve — and to make decisions about NPSH margin, parallel versus series staging, and VFD setpoints that directly affect energy costs, equipment life, and system reliability. This guide builds directly on the pump curve and system curve concepts from the previous tier and applies across water treatment, distribution, collection, and wastewater treatment operations alike.
The Operating Point in Depth
Recall that a pump's performance curve, Hp(Q), slopes downward as flow increases, while a system's demand curve, Hs(Q), slopes upward due to rising friction losses. The operating point is the unique flow and head where these two curves intersect — it is the only point at which the pump can actually run in that system, because it's the only flow at which th