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The USGS has posted an excellent video of how the discharge can vary widely over a short period of time at an edge-of-field site. The site uses a H flume provided by Openchannelflow to measure and analyze the discharge off a field near Fort Wayne, IN.

The ultrasonic flow meter is one of the instrumentation workhorses for measuring open channel flows in general, and flumes in specific. Ultrasonic flow meters are generally low cost, robust, and provide a reasonable level of accuracy (+/- 0.02’ for a head change of less than…

Built in 1953, the Pensacola Plant is situated on a 2200 acre tract, 12 miles north of the City of Pensacola, on the Escambia River. Solutia is the world's largest producer of nylon carpet staple. The facility produces nylon polymer chips for the automotive and electrical…

Let’s be honest: metering manholes (from an upfront, material cost standpoint) aren’t cheap. While no one would argue that metering manholes don't provide substantial benefit to their users, part of what you are paying for is a unit that is ready for immediate installation…

In general, most Parshall Flumes are designed to have free discharge (flow not restricted by downstream conditions). Sometimes, however, changes in the downstream hydraulics may submerge a flume, or a flume may be designed to operate under submerged conditions due to upstream…

Using flumes to measure flows in cold climates brings a set of challenges not otherwise faced in warmer climate applications. Some of the problems that can be encountered when using flumes in cold climates include:

In selecting a flume, it is generally advisable to choose the smallest flume capable of handling the anticipated flow rate. However, this means that the even at its widest the flume is normally narrower than the channel is wide. The problem then becomes how to transition flow…

The 2-inch Parshall Flume is the second smallest of the Parshall Flumes. Like the 1-inch, the small size means that it is somewhat limited in use. When used to measure sanitary flows, the flow entering the flume must be well screened, or it will clog. The 3-inch Parshall Flume is…

As we’ve detailed before here and here, most flumes currently used to measure the flow of water in non-full pipes were not originally designed to do so. Other than the Palmer Bowlus, these flumes were designed to measure flows in streams, culverts, and natural channels. Over…

Combining elements of both a flume and a weir, the H series of flumes (HS / H / HL) are well adapted to measuring a wide range of flows accurately. As a result, H flumes are frequently used where wide swings in the flow rate are expected – such as edge-of-field and storm water…

The Konkola mine is situated in Chililabombwe, approximately 26 kilometres north of Chingola, and is the most northerly of the KCM's Zambian Copperbelt mines. These mining operations exploit the Chililabombwe ore body by underground methods. Shaft depths exceed 1,010 meters…

With Free Flow, Inc. (formerly of Gretna, NE) closing at the end of 2012, Openchannelflow would like to extend a welcome to its former customers who are in need of assistance with their flow monitoring needs. Openchannelflow offers these as well as many other products for the…

Sometimes measuring discharge from lakes and ponds can be challenging…particularly when there isn’t a convenient spot to put a discharge weir or flume.

Many kinds of flume are in use today around the world, in applications as diverse as dam seepage monitoring to industrial pre-treatent discharge. These flumes can be divided into two different classes: short throated and long throated.

The factory-direct method of dealing with our customers works well in many instances, but there are times when only "boots-on-the-ground" will do.

For many engineerings and end-users the default configuration for flume always includes a stilling well...and why not? When they work, they work great - providing a convenient area to measure the flow in a flume. When they don't work....well that's another matter.

In flow measurement, freeboard is defined as the distance from the top of top of the water to the top of the flume or channel that it is in. For flumes, freeboard allows minor surface turbulence to exist without flow overtopping the sidewalls. The amount of freeboard is usually…

The combination of a flume with an ultrasonic flow meter is a very reliable method of measuring wastewater flows. The set-up can be low cost and provide good overall accuracy. A specially shaped, fixed hydraulic device that accelerates subcritical, open channel flow in such a…

Cribbing (bracing) a flume is one of life's little chores. It isn't something we want to do, but rather something we have to do. If it is done well, the results are great. If it is done poorly (or not at all), trouble is bound to follow. In installing the Parshall flume below,…

“Long-throated flumes have many advantages compared to other measuring devices (for open channel flows), including Parshall flumes. Long-throated flumes are more accurate, cost less, have better technical performance, and can be computer designed and calibrated.”