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The 3-inch Parshall Flume is one of the last flumes developed in the Parshall series. The flume can be used equally well to measure sanitary flows as well as surface waters. It is important to note that the 3-inch Parshall flume is the smallest Parshall Flume size that can be…

The 9-inch Parshall Flume is a popular size in the Parshall Flume family. The flume is equally at home measuring surface waters, wastewater flows, and water rights.

The 12-inch Parshall Flume is one of the most popular sizes of the Parshall Flume family. The flume is equally at home measuring sanitary wastewater at a municipal treatment plant as it is measuring water rights on The Western Slope. Applications The flume is regularly used to…

For years Openchannelflow has offered staff gauges integrated into our flume, weir, and manhole products.  Over time, though, we have been asked to expand our offerings to include free-standing staff (level) gauges. Openchannelflow staff gauges are availalbe in a range of:…

On the face of it, mounting a staff gauge on a weir plate to get the head / flow rate seems like a good idea.  It works for on a flume, why wouldn’t it work on a weir? The problem is, as we have seen earlier, the water level in a weir pool draws down as the flow…

A common problem in using weirs to measure water flows is reading the flow level too close to the weir plate.  To understand why this is a problem we need to look at what happens as flow travels through the weir pool and then over the weir crest. In a properly formed,…

We often talk about how OCF tried to sweat the small things.  One of the items that we have focused on is our flow meter sensor mounting brackets.  Many of the designs currently on the market show, what we believe to be, a "good enough" philosophy - that the brackets…

The Palmer-Bowlus flume – quite possibly the second only behind the Parshall flume for measuring wastewater flows – suffers from a number of problems when it comes to its operational use. Some of the problems include:  proprietary design, high minimum flow rates,…

One question we get asked on a regular basis is:  can flow free fall off the end of a Parshall flume?  The answer is: yes – and if possible, this is the preferred method of discharge!  To understand why, we need think about how a Parshall flume operates:…

The H flume is a class of flumes developed by the Soil Conservation Service (USDA) to measure runoff from catchments and experimental plots.  Really more of combination between a flume and a weir, the H flume provides excellent low flow handling, solids passage, and a wide…