Flumes & Weirs

We sell, design, and install many different types of flumes and weirs, available in either steel, fiberglass, and concrete. We also provide a variety of sensors, dataloggers, and data retrieval systems (including via internet) for monitoring and recording flow rate through a flume or weir.

Open Channel Flow using Flumes & Weirs (Primary Measuring Devices)

Note from the USBR Measurement Manual: “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 (Ramp 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.

Designing and setting Parshall flumes for submerged flow measurement is not usually recommended because less expensive, long-throated flumes can be designed that approach or exceed 90 percent submergence limits with a single upstream head measurement. Another consideration is the absolute required drop in water surface is usually less for the long-throated flumes, particularly the modified broad-crested weir styles. A broad crested weir is often referred to as a Ramp flume.

Flumes

Ramp flumes (broad-crested weirs), cuttroat flumes, Parshall flumes, H-flumes, trapezoidal flumes, and other flumes—made of steel, fiberglass, or concrete.

weir box for flow

Weirs

Flow measuring weirs. Steel and fiberglass options available. Call us for help selecting a weir type.

Broad-crested weirs or ramp flumes are listed under Flumes.

Alternatives

Flow probes and area velocity meters. In some applications these can be used to measure flow rate in place of a flume or weir.

Sensors & Accessories

We have a variety of sensor systems used for monitoring, logging and reporting flow rate through a flume or weir. Most of these sensors (depending on the specific model) send a signal that is recorded by a datalogger, and the data can be retrieved later in person. It can also be transmitted live via radio or internet, allowing you to monitor flow rates with a radio receiver, or even from a cell phone or web browser.

Flume Sensors

Sensors for monitoring flumes and weirs, including ultrasonic sensors, floats and pulleys, pressure transducers, bubblers, and radar level sensors.

Dataloggers & Telemetry

Hardware for recording sensor data and transmitting it, including enclosures, solar panels, batteries, etc.

Stilling Well

Stilling Wells

Hardware for recording sensor data and transmitting it, including enclosures, solar panels, batteries, etc.

Resources

DIY Measure Flow

Learn how to estimate flow rate through a channel or river without specialized tools or equipment by using the Float Method.

Flumes Brochure

Flow Measurement Brochure

Here is a link to the USBR Water Measurement Manual online. You will find a lot of useful information on the measurement of water. (Bureau of Reclamation)