This utility operations manual describes in detail the design and operation of commonly used flowmeters in water systems. This manual covers venturi, modified venturi, orifice plate, electromagnetic, turbine and propeller, transit-time ultrasonic, vortex, averaging Pitot, and averaging insertable electromagnetic meters. It explains basic theory, advantages and disadvantages, and recommended installation and maintenance practices for each type of meter. Discussions of flow characteristics, signal output and transport, electronic meters, piping configurations, associated wiring, and power connections are included.