A flume can be used to measure the rate of flow. Specific designs include the Venturi Flume, Parshall Flume, Palmer-Bowlus, trapezoidal, and H-Flume. See flow measurement. A sewer pipe can be used as a flow measurement flume by using the Manning formula.
In competitive swimming, specialized flumes with transparent sides are often employed by coaches to analyze a swimmer's technique. The speed of the flow is variable to accommodate the full spectrum of swimming styles and ability.