Your Choice for Economically Designed Palmer Bowlus Flumes

Developed in the 1930’s, this flume was specifically designed to be a simple and effective wastewater flow-measuring device.

Wastewater Flow Measuring Device

The Palmer-Bowlus flume takes its name from its inventors, Harold Palmer and Fred Bowlus. The flume is essentially a restriction in the channel and is sized according to the width of the flume (typically, but not always, the width of the pipe it is connected to).

Three Palmer-Bowlus Styles

palmer bowlus flume design
Economically Designed Palmer Bowlus Flumes
palmer bowlus flume

4D+1 inch Permanent Style

  • 2” top and end flanges
  • Integral approach section
  • Point of measurement inside of flume

2D+1 inch Portable Style

  • 2” top and end flanges
  • Shorter lay length than 4D+1” style
  • Point of measurement upstream (outside) of flume
    • Cannot be provided with bubble or sample tubes, submerged probe or Drexelbrook cavities, or staff gauges
Available with outlet bulkhead to connect to existing pipe

Insert Style

  • 2D+1” length
  • No top or end flanges
  • No support ribs
  • Intended to install into the lower half of an existing pipe
  • Point of measurement upstream (outside) of flume
    • Cannot be provided with bubble or sample tubes, submerged probe or Drexelbrook cavities, or staff gauges
Not available with inlet or outlet bulkheads

Selection Criteria

For new construction the 4D+1″ style is preferable due to the integral approach section. The 2D+1″ style is more common in retrofit constructions where space is a concern, although problems can occur in that the head measurement is made upstream from the flume itself. Unlike the 4D+1″ and 2D+1″ styles, the Insert style does not have inlet or outlet flanges and is intended to fit into existing pipe.

Technical Details

  • Ultrasonic mounting brackets
  • Bubble tubes
  • Sample tubes
  • Submerged probe cavities
  • Stilling wells (attached and detached)
  • Staff gauges
  • Removable probe holders
  • Inlet and outlet bulkheads
  • Pipe stubs
  • Flanged end connections
  • FRP grating
  • Riser boxes
  • Transition entrances
  • Nesting
  • Multi-piece construction
  • Chemically resistant gel coat
Size Recommended Flow Rates
44” 45 – 55 GPM
66” 615 – 148 GPM
88” 824 – 213 GPM
1010” 1056 – 521 GPM
1212” 1289 – 817 GPM
1515” 15148 – 1450 GPM
1818” 18239 – 2271 GPM
2121” 21358 – 3322 GPM
2424” 24505 – 4622 GPM
2727” 27684 – 6259 GPM
3030” 30868 – 8116 GPM
4242” 422023 – 18794 GPM
4848” 482858 – 25154 GPM
5454” 543873 – 35199 GPM
6060” 604993 – 45673 GPM
7272” 727877 – 72046 GPM
For sizes above 72” consult the factory

Additional Examples

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