Flumes
Ramp, Cutthroat, Short Parshall - the Montana, and Parshall
A NEW Ramp Flume Design! Hot Diggity!
Constructed from:
Galvanized or stainless steel
14 to 11 gauge
Galvanized or stainless steel
14 to 11 gauge
Sizes:
In Stock - As of April 2025 - In stock items change, gone today here tomorrow
Cutthroat Flumes
8" throat x 36" - 3 cfs, Model GBECT-8
16" throat x 36" - 6 cfs, Model GBECT-16
Short Pashall, The "Montana" Flume
9" throat - 7.75 cfs, Model GBESP-9
Ramp Flume
12.75" throat width - 4,5 cfs, Model GBRF-1275-272
18.75" throat width - 6.0 cfs, Model GBRF-1875-272
Other sizes available
Custom - not currently in stock, built on request
24 inch throat x 54 - 16 cfs, Model GBECT-24
12 inch throat x 54 - 8 cfs, Model GBECT-12
Other Custom sizes on request
In Stock - As of April 2025 - In stock items change, gone today here tomorrow
Cutthroat Flumes
8" throat x 36" - 3 cfs, Model GBECT-8
16" throat x 36" - 6 cfs, Model GBECT-16
Short Pashall, The "Montana" Flume
9" throat - 7.75 cfs, Model GBESP-9
Ramp Flume
12.75" throat width - 4,5 cfs, Model GBRF-1275-272
18.75" throat width - 6.0 cfs, Model GBRF-1875-272
Other sizes available
Custom - not currently in stock, built on request
24 inch throat x 54 - 16 cfs, Model GBECT-24
12 inch throat x 54 - 8 cfs, Model GBECT-12
Other Custom sizes on request
Applications:
1. Irrigation ditches and canal
2. Water rights
3. Instream flow measurements
4. Flow from tile drains
5. Management of cropping and water usage
1. Irrigation ditches and canal
2. Water rights
3. Instream flow measurements
4. Flow from tile drains
5. Management of cropping and water usage
Why The Ramp Flume? And The Con
We recommend free flow conditions only for the best accuracy (we say that a lot).
Download the flume_document_6-15-2023 for current pricing and information.
- The ramp flume was developed during the mid 1960 - 70s
- The ramp flume is given to computer modeling for virtually any application and flow.
- Well suited for flat and low gradient ditches and canals if properly designed, it is highly resistant to submergence.
- The USBR recommends this design due to a high degree of versatility and computer modeling (USBR) We recommend free flow conditions only!
- Use in free flow conditions only,
- Accuracy of +- 2 percent. The most accurate of the flume designs if properly installed.
- Cost effective to build and install.
- The Cutthroat flume was developed during the mid 1960's at the Utah Water Research Laboratory, Utah State University, Logan, Utah by Skogerboe, and others. Further work was done at Colorado State.
- Sizes are standardized in original research papers and work is ongoing.
- The primary objective of their development was construction simplicity compared to the complexity of a Parshall flume. (USBR)
- Several researchers do not recommend due to hydraulic complexity. (USBR) We recommend free flow conditions only!
- Subject to submergence just like all flume designs if improperly installed and used.
- Use in free flow conditions only, with an accuracy of +- 3 percent.
- Cost effective to build and install.
- Developed beginning in 1915, Dr. Ralph Parshall of the U.S. Soil Conservation Service
- Standardized engineering specifications found in: ASTM D1941 − 91 (2013) and U. S. Department of the Interior, Bureau of Reclamation, WATER MEASUREMENT MANUAL, A WATER RESOURCES TECHNICAL PUBLICATION: A guide to effective water measurement practices for better water management.
- "Although Parshall flumes are in extensive use in many western irrigation projects, they are no longer generally recommended because of the advantages of long-throated flumes previously cited and the disadvantages of Parshall flumes to be subsequently discussed. Some states specify the use of Parshall flumes by law for certain situations." (A direct quote from USBR Water Measurement Manual)
- Sub-Type - The Montana, or short parshall. The Montana is cost effective to build but must be used in free flow conditions only.
- Subject to submergence - must be properly installed.
- Use at free flow only with a normal accuracy of +- 3-5 percent.
- All flume designs can experience a condition called submergence, which is defined as downstream conditions invalidating the rating equations, i.e., slow moving water backing up into flume.
- All flumes must be properly installed and maintenance performed on a regular basis.
We recommend free flow conditions only for the best accuracy (we say that a lot).
Download the flume_document_6-15-2023 for current pricing and information.
Downloads
| spring_2024___truncated.pdf |
| cuutthroat_flume_photos_etc__.pdf |
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Visit us often and see what we are doing in the development and fabrication of more flumes. We are always adding options.
Tell us what you need, we are open to custom designs to meet your needs.
Have water? We help you measure!
Tell us what you need, we are open to custom designs to meet your needs.
Have water? We help you measure!
