the level floor of the converging entrance section joins the inclined floor of
the throat section. Still wells may be installed alongside a flume to view
water level if flume surface is frozen over or water surface is thick with
2.2 Palmer-Bowlus Flume. The Palmer-Bowlus flume is used primarily in
circular conduits such as storm and sanitary sewers. Both sidewall and bottom
contraction are used (Figure 7-5).
3. LIMITATIONS. The major limitation of flumes is that they are designed for
individual locations, such as general information metering of storm and
sanitary sewers or irrigation purposes.
4. INSTALLATION. Since flumes are not off-the-shelf meters, installation is
governed by design. Upstream and downstream cross-sections and lengths are in
the design specifications for each location. Follow design specifications for
grade height and zeroing of still wells, if used.
5. MAINTENANCE. All types of head and area meters are used for open flow
measurement. Their operation depends on the absence of interference at the