How to Install a Trapezoidal Flume

A successful flume installation requires that the flume be set correctly.

Installing the flume

• The flume should be set so that it is centered in the flow stream.

• The upstream floor of the flume should be set high enough so that the flume does not operate under submerged flow conditions.

• The outlet of the flume should be set at or above (ideally) the invert of the outlet channel / pipe to help transition solids out of the flume.

• The somewhat longer end of the flume must be set upstream.

• The floor must be level from front-to-back and from side-to-side (using a level on the floor - not the top - of the flume)

• The flume must be braced internally (plywood and lumber are typically used) during installation to ensure that distortion does not occur.

• The flume must not float out of its intended final position during installation.

• Open channel flow (non-full pipe) conditions must exist at all times.

Bracing

The bracing on the top of the flume should be left on until the installation has been completed.  If the flume is set in concrete, the bracing may be removed once the installation has been completed.  For installations where the flume is free-standing or otherwise not set in concrete, the bracing should be left in place.  If the bracing is removed, verify the dimensional accuracy of the flume after the removal.

Joints

Trapezoidal flumes supplied with bulkheads, or transition sections must remain sealed between the joints.  While these joints may be sealed initially at the factory, a final visual inspection of all joints should be done before installation.  Where required, apply one or two continuous beads of silicone on all seating surfaces before proceeding with the installation.