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Openchannelflow offers a number of different flow conditioners to help to normalize the flow before it enters a Parshall flume. Some of the conditioners are in-flume accessories, while others are installed upstream of the flume itself.

With the advent of the Packaged Metering Manhole (PMM) in the 1960’s, monitoring wastewater discharge compliance by industrial customers became considerably easier. By factory integrating a primary device (usually a flume or weir, but mag meters can also be installed), into a…

The freeboard is the difference in height between the top of a flume or weir and the highest water level anticipated. Freeboard is a guard against overtopping by waves, unexpected rises in the water level, or miscalculation in the maximum anticipated flows. Freeboard is also…

While not as varied as H flumes are in terms of their mounted, Parshall flumes can be installed in a number of creative ways to meet your flow measurement needs. Versitle in instalation and widely used, the Parshall flume is most famous of the short throated class of flumes and…

In terms of installation and mounting, one of the most versatile flumes is the H Flume. This versatality in installation, combined with a wide range of styles and sizes, make the H flume one of the most popular flumes to meausre water and wastewater flows.

A Staff Gauge is a measuring tool, similar to a tape measure, used to provide a visual indication of the depth of water (typically in a river, flume, or weir). Staff gauges are inexpensive, static, permament, and don't require power and can be an excellent way to measure flow…

During periods of rapid water level change, the level in a stilling well may lag behind those in the channel that it is measuring. This phenomenon is known as stilling well lag and is a result of head loss in the intake system. Stilling well lag may occur when the water level in…

From time to time, Openchannelflow comes across videos, discussions, or other information that we think may be useful for our readers. Keep in mind that while we present this information for your review,

Openchannelflow is pleased to announce that Whitney Equipment of Bothell, WA has signed as a full-line representative for the Pacific Northwest. The professionals at Whitney Equipment are specialists in flow meters, level controls, and automatic sampling representing…

The Federal Water Pollution Control Act of 1948 was the first major U.S. law to address water pollution. Growing public awareness and concern for controlling water pollution led to sweeping amendments in 1972. As amended in 1972, the law became commonly known as the Clean Water…

Location: Shaver's Creek Environmental Center, Petersburg, PA, USA Applicaton: Watershed runoff flow monitoring and characterization

Openchannelflow is please to announce that Midwest Municipal Instrumentation has entered into full-line representation agreement for the State of Michigan and northwestern Ohio.

In a suppressed rectangular weir, the nappe stretches from channel wall to channel wall. On the downstream side of the weir, the air under the nappe will become entrained in the nappe as it passes over it as it spills into the downstream channel.

Packaged flow measuring manholes are a drop-in place solution to the need to measure, sample, and characterize the flow of water through a collection system. Flow measurement is commonly done where industries discharge to a POTW's collection system or at critical sections in a…

The purpose of a Parshall flume is to measure the flow of water in an open channel (or non-pressurized pipe). This water can be from a variety of sources, including: rivers, streams, canals, channels, field runoff, mine discharge, dam seepage, springs, wastewater, and industrial…

One problem that we see again and again is how to measure open channel flow in partially full pipes. For applications where a device can extend off the end of the pipe a number of solutions are used, including: California pipe (which is extends vertically up from the pipe before…

Recently an industrial customer of Openchannelflow installed one of our fiberglass Packaged Metering Manholes and documented the steps involved in its installation.

One of the most common uses for flumes is to measure the flow of sewage though collection systems. While we may tout the advantages of Packaged Metering Manholes - and they are considerable - the higher initial cost means that when an existing manhole is available, a flume is…

Parshall Flumes are a class of short throated flumes. Originally developed in the 1920's, the Parshall Flume has become the most researched style of flume leading to its wide acceptance and use in a variety of applications.

On the face of it, the H flume looks to be a good choice when selecting a device to measure storm water flows. At its core, a H flume is a hybrid device: a combination of a flume and a weir – melding the best of each into a single device. The flume has a wide turndown ratio…