Weirs are a type of hydraulic structure, like flumes, that consist of an obstruction placed across an open channel. Typically, much smaller than a conventional dam, the weir is more a bulkhead with a specially shaped opening or notch over which water flows. This is used to measure the flow rate in the open channel itself.
These can be customized into different types and sizes depending on the type of water flow being measured. Tracom Inc. manufactures a complete line of customized weir boxes to fit many different roles, and has provided the following information to help potential customers figure out their specific needs.
What Are Some More Details About Weirs?
A trained professional can use weirs to simply and efficiently measure flow rates in small to midsize open channels. Typically, the calculation relies on the shape of the weir itself, the depth of water behind the weir, and the edge or surface over which the water flows, which is called the crest. As such, it is very important that the weir crest is kept clean and undamaged, even from trace amounts of rust, since any kind of roughness will cause calculations to go awry.
Are There Any Drawbacks to Using a Weir?
Due to their construction, weirs can potentially pose some issues for local animal life, though the installation of a simple fish ladder tends to solve this problem easily enough. It’s also best to avoid swimming or boating anywhere near a weir as strong circulation around weirs could prove fatal. What’s more, the accumulation of debris and other materials around a weir over time can lead to inaccurate water flow readings and damaged weir boxes.
What Are the Common Varieties?
Weirs come in all shapes and sizes, and are typically defined by the shape of their opening or notch, which are usually sharp- or broad-crested. A sharp-crested weir is one in which the water springs clear of the crest due to a sharp upstream corner or edge. The most common sharp-crested weirs are the rectangular weir, trapezoidal weir, Cipoletti weir, and the triangular or 90-degree V-notch weir. The broad-crested weir, on the other hand, are fairly long and horizontal or nearly horizontal. Weirs can also be contracted or suppressed.
As their names suggest, the crest and sides of a contracted weir are far away from the bottom and sides of the channel, while a suppressed weir has sides that are right by the sides of the channel.
How Can Tracom Inc. Help You?
Now having learned a little bit about weirs, what’s the next step? Simple. Let Tracom Inc. help assess whether or not a customized weir would be beneficial, and if it is, look into possible installation at a future date. Regardless of open channel type, Tracom Inc. can help find the measuring system that will work best.
Contact Tracom Inc., either by leaving an online message or calling directly at 1-877-435-8637, to get started today. We very much look forward to helping you!
