Foam in Flumes and Weirs

If you use flumes or weirs to fulfill your flow management needs, then you’re probably aware there are a variety of issues that can cause source-errors in this devices. However, one of the most overlooked hazards for flumes and weirs is foam. When you experience foam in your system, it can cause major problems, impacting the accuracy of your readings and causing your operators to waste time on maintenance.

To make sure you get the accuracy that you need out of your flumes or weirs, you need to learn more about the risks of foam and how to prevent it from forming. Learn about limiting foam in flumes and weirs, and discover how you can improve your operation’s success with the right tools.

Types of Foam

Before you can learn how to prevent foam in flumes and weirs, it’s a good idea to examine the types of foam that can form in your system. Generally, foam in your flumes or weirs will either be biological or chemical. Both pose big threats to your system, but form in distinct ways.

Chemical foam is typically what people imagine when they think of foam, as it is white and bubbly. This type of foam is usually eliminated by using a defoaming agent at the point where the foam forms. Biological foam is often a dull, brown color and can appear very slimy. These foams usually form because of hydrocarbons in your system. Combatting biological foam is very difficult, as they do not respond to foaming agents.


The biggest risk of having foam in your system is that it can alter the accuracy of your measurements. This is particularly true when you use a flow measurement device like an ultrasonic flow meter. Ultrasonic flow meters rely on a level water surface to take accurate readings. If the surface of your flow is turbulent or has foam, your ultrasonic flow meter will not be able to function correctly.

If foam is a persistent risk in your system, you should consider switching from an ultrasonic flow meter to a tool like a submerged probe or bubbler.

Stilling Wells and Baffles

It is also possible to mitigate the risks of foam by installing devices like a stilling well or baffle plate in your flume or weir. With a stilling well, you are separating a portion of your flow in a chamber that will be free from turbulence and foam. An underflow baffle can be installed just before the point of measurement to prevent foam from passing by and allowing your measurement tool to take an accurate reading.

Stop Foam in Flumes and Weirs

Foams in your flumes and weirs can cause big problems for your operation, especially in regards to the accuracy of your readings. The best way to prevent the formation of foam in your flumes and weirs is having the right tools at your disposal, which is why you need to start shopping with Tracom, FRP.

In the Tracom product catalogue, you’ll find a great selection of flow management tools, including flumes, weirs and other devices. Request a quote from Tracom today so that you can stock your operation with the tools that will stop foam in its tracks.