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Openchannelflow welcomes Guthrie Sales and Service, Inc. into our growing network of world-wide representatives! Guthrie Sales and Service will cover Tennessee and all but the western tip of Kentucky for Openchannelflow.

Weir Boxes are the preferred method of monitoring seeps from concrete and earthern dams. Their ability to meaure low flows and retain sediment for future investigation make them a natural choice for the application. The small foot print and ability to have differnt inlet / outlet…

Steel, while not used in wastewater applications, is a common material of construction for flumes used in water rights and irrigation applications. Both painted and galvanized steel are used for these applications; of the two, though, galvanized steel is the most common. Painted…

One problem application we see time and time again is measuring the flow out of a UV disinfection system. To keep the UV bulbs cooled and to increase the treatment efficiency of the disinfection system, usually the UV system provided has V-shaped overflow weirs just downstream of…

The installation of a Palmer Bowlus flume is a straight forward and can be accomplished with a minimum of effort. The straight-through, u-channel design means that there are no changes in elevation to accommodate and that the flume is well suited for installation in manhole…

The three most common devices used to measure water rights are: Parshall flumes, V-notch weirs, and Cutthroat flumes respectively. But this doesn’t mean that other devices are used or aren’t suitable for measuring water right flows!

The most common way of transitioning flow into and out of a Parshall flume is to simply form a channel up to and away from the flume. This works in many situations, and was in fact the way that Dr. Parshall himself installed his flumes. But what about when you need to measure…

Irrigation flumes can be categorized into two groups: those used for Water Rights and those used to measure in-field flows (furrows).

A nested (or dual-range) Parshall Flume is one where a smaller, lower flow range flume has been mounted into a larger, higher flow range flume. By nesting the two different flumes together, over time two substantially different ranges of flow can be measured in one installation.

As State Engineer’s Offices become more concerned over accurate measurement of water rights withdrawals, flow-measuring devices are becoming mandatory. These flow-measuring devices typically take shape as flumes – with the Parshall and Cutthroat flumes being most common. Both…

Fiberglass Packaged Metering Manholes are a great solution to the problem of measuring piped flows below grade and provide a unique set of benefits to consulting engineers who specify them. Accuracy, in this context means, installation accuracy by the contractor and the flow…

When using a Parshall Flume to measure pipe flow, it is important that sufficient upstream distance be provided to allow the flow to become tranquil and to assume a normal velocity profile as it enters the flume.

The USGS Portable Parshall flume is a modification of the standard Parshall flume where the discharge section has been removed. The purpose of the modification is to reduce the weight of the flume and to make it easier to install.

The Stream Institute at the University of Louisville is an interdisciplinary applied research program in the Department of Civil and Environmental Engineering. The work of the Institue is primarily concerned with the mitigation of human effects on streams, wetlands, and…

Every year at Openchannelflow we talk with several hundred consultants, researchers, contractors and end-users about their flow monitoring needs. Because we work extremely hard at answering all questions "flow” on this web site – and this blog in particular - we are often…

Parshall Flume Metering Manholes are an excellent solution to the problem of how to monitor below-grade piped flows. Integrating the popular Parshall flume into a fiberglass manhole, Parshall Flume Metering Manholes are complete, factory-integrated structures capable of direct…

End Adapters are specially shaped transitions that are molded or secured to the inlet and outlet ends of Parshall flumes to connect then to inline piping so that flow can be measured. End adapters serve to transition flow from the round pipe to the rectangular cross-section of a…

Parshall Flumes – like all flumes - are obstructions placed in a flow stream that produce backwater. This backwater extends upstream of the flume and raises the water surface in the approach channel. The difference in water surface elevation with and without the flume is…

In North America, large Parshall Flumes – those with throat widths larger than 144-inches – are primarily used to measure the diversion of water from streams, lakes, and other primary sources of surface water to smaller irrigation distribution systems. Most of these…