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Less well known than their more numerous Rectangular throated brethren, Trapezoidal Cutthroat flumes are a class of (3) flumes that combine the low flow sensitivity of the Trapezoidal flume with the simple, throatless design of the Cutthroat flume.

Small Parshall Flumes, those from 1-inch to 3-inches in size, are well suited to a variety of applications, from stream gauging to industrial pretreatment monitoring. The flumes posses good flow ranges, are able to measure low heads / flow rates with accuracy, and are available…

In his 1936 report, The Parshall Flume, Dr. Parshall reported the results of a limited series of tests conducted on a 2-foot Parshall flume where the approach velocity was varied. His observation was that discharge through the flume was not significantly affected when approach…

Trapezoidal flumes are popular choice when industrial users need to measure pretreatment discharges. The trapezoidal shape of the flumes provides sensitivity to the low flow rates (like during a plant shut down), while retaining the ability to handle large, peaking flows (from…

Many people confuse a flume’s resolution with its accuracy and use the terms interchangeably. The two, however, are distinct from each other. A flume may have good resolution, but poor accuracy, and vice versa. Resolution is a how much change in head is developed in the flume…

It’s not uncommon in catchment, surface water, and watershed applications to only need to monitor a site for several seasons or years. Sometimes, in fact, there is a need to be able to dismantle the installation after the monitoring period has been completed. When this is the…

For flume and weir applications where the flow entering the device may not be as well distributed as one would like / or where the velocity profile needs adjustment, perforated baffle plates can be a good choice. Used in a series of two or more, perforated baffle plates help…

Warner College of Natural Resources - Colorado State University Warner College of Natural Resources (WCNR) at Colorado State University (CSU) is the largest named and most comprehensive natural resources program in the United States. WCNR serves as a leading institution in the…

One advantage that the Cutthroat Flume has always had over other short-throated flume like the Parshall or Trapezoidal was the ability to develop intermediate width flumes for one of the four standard lengths. But what if the standard lengths don’t yield a Cutthroat flume that…

RBC flumes are small, portable long throated flumes designed specifically for use in small earthen channels and furrows. The five flumes are scale models of each other, with each flume possessing a trapezoidal throat varying in size, bc, from 50 to 200 mm [1.968 to 7.874-inches].

Thin-Plate Weirs, when properly installed and maintained, are one of the most accurate means of measuring open channel flows. Under field conditions, though, without proper sizing or regular maintenance a thin-plate weir will become increasingly less accurate over time.

A problem with the application of thin-plate weirs in the field is the lack of proper conditioning of the flow before it reaches the weir crest. Baffles, placed upstream of the point of measurement, can be used to correct both poor approach velocity profiles and surface…

Freestanding staff gauges are a good solution to the need to measure level in a flume, weir, or channel. They are also useful in stream gauging or as replacements for other gauges that are damaged or no longer readable.

Reinforced Weir Boxes are a convenient way of measuring seepage flows out of a dam when the pipe is just below grade. Reinforcing the sidewalls of a weir box can allow the structure to withstand the pressures exerted by the soil in shallow burial applications.

Flumes of all styles are used in the measurement and treatment of wastewater. Wastewater applications can be municipal or industrial in nature and their content can be sanitary (including mixed) or non-sanitary.

The video below highlights the ability of the H Flume to measure a wide range. The ability to accurately measure a wide flow span makes the H flume uniquely suited to edge-of-field installations. Edge-of-field monitoring serves as a bridge between larger watershed studies and…

Stainless steel is often viewed as the material of choice for Parshall flumes when severe corrosion is expected or when abrasion is a concern. For Parshall flumes, the split between T-304 and T-316 stainless steel is about 60 / 40, with more flumes being constructed from T-304.

Although initially developed to measure runoff from watersheds and experimental plots, the H Flume has proven to be quite flexible in its mounting configurations. For below grade applications, HS and H Flumes up to 2-feet in size can be:

Open feedlots are common throughout North America. Although they provide an economical way to feed and raise a variety of livestock, such operations generate large quantities of runoff that have considerably elevated nutrient levels (ammonia, nitrogen, and phosphorous) as well as…

Edge-of-field (sometimes referred to as catchment) monitoring is where flow from a particular field is routed to a monitoring station located at the edge of the field to allow for the characterization of the runoff flows. Edge-of-field monitoring is used in a number of…