Parshall Flume Modifications

For water management operations both large and small, there is no more useful flow management tool than the Parshall flume. Providing flexible installation options and accurate readings, using a Parshall flume means being able to maintain a high level of success well into the future.

While the Parshall flume is one of the versatile flow measurement tools in existence, it’s not suitable for every situation, which is why two modifications have been made to this flume type. Learn about the most popular Parshall flume modifications and find out which of these tools is right for your specific water management needs.

USGS Portable Parshall Flume

The first modification to the Parshall flume that we will discuss is the USGS portable Parshall flume. Unlike other modified flumes, the changes made to the USGS Parshall flume are relatively minor. The only real difference between this flume and the regular Parshall flume is that the USGS flume omits the diverging section.

While the original USGS Portable Parshall flume was only produced in a 3-inch model, it is now also available in a 6-inch model. However, because all research is based on these two sizes, your operators will need to be careful when using this Parshall flume modification, as size differences may influence how this flume operates.

In addition, it is not possible to correct the USGS Parshall flume for submergence. This means that you should avoid using this type of flume in situations where the submergence ratio is more than 0.5 Ha.

Using the Montana Flume

The other type of popular modification to the Parshall flume is the Montana flume. The Montana flume was specifically designed for systems where free-spilling discharge can be maintained under every flow condition. Similar to the USGS portable Parshall flume, the Montana flume does not have a diverging section. This flume modification also eliminates the throat, meaning the only section that’s left is the flat-floor converging section.

One of the benefits that the Montana flume holds over the USGS flume is that the Montana flume is much lighter. However, the Montana flume is also not resistant to submergence. Another advantage of the Montana flume is that the flow equations are exactly the same as a standard Parshall flume, which cannot be said for the USGS flume. While there are no restrictions on the size of a Montana flume, you will usually not find these flumes larger than 24 inches.

If you’re interested in using a Montana flume in your system, you must be aware that your system needs to guarantee free-spilling discharge under all flow conditions. Otherwise, the flume will not be able to function correctly.

Choosing Your Parshall Flume Modifications

If you’re interested in using one of these modified Parshall flumes in your system, you should get advice about which option is right for you from the professionals at Tracom, FRP.

Take a few minutes to browse the Tracom catalogue, and you’ll find some of the highest quality fiberglass flow management tools on the market today. Whether you want the standard Parshall flume or a modified version, we have a device that matches your needs. Request a quote from us today to get started.