The Cartridge Meter is the first open channel flowmeter to utilize hybrid technology. The new technology combines a traceable U.S. Bureau of Reclamation flume/level system for low flow applications with the more accurate EPA proven transit-time chordal velocity method for high flow applications. This new hybrid technology system allows for precise and highly accurate flow measurement during extremely low flows, high flows, surcharges, reverse flows, stagnation and non-uniform hydraulic profiles.