Venturi Flumes

Venturi flumes are designed to accurately measure higher flow rates in open channels.

They work by being a particular shape that restricts the flow of water in such a way that it creates an accurate point for measurement where the flow is forced to reach a sub-critical state.

Also known as critical depth rectangular flumes, they are manufactured in a range of different materials including polished GRP, PVC or stainless steel, and can be packaged up to form a full regulatory flow conformance system.


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Suitable for measuring flow with solid waste

SIRIS venturi flumes are recommended for liquid flow measurement within open channels, particularly where suspended solids material is being transported, and are almost universally used in measuring the in-flow to sewage treatment works.


Options for low flow rates available

The dimensions of our venturi flumes are easily adapted to the size of the existing channel and we can provide flumes for a range of flow rates in different manufactured materials, such as stainless steel.

We do a range of flumes that cover various flow rates and applications. Two of our standard-sized small flumes can be used for final effluent flow measurement or clean water discharge applications where the flow rates are significantly low, which would often require alternative flow measurement systems to be applied.

Accurate & reliable data

Flumes come in varying sizes and structures depending on the volume of flow, and the correct choice and installation of the flume is essential to guaranteeing accurate data. Using our team of experienced and certified personnel, we work with our customers to ensure the optimum design specification and installation of our flumes to ensure absolute accuracy of your flow measurement system.

All SIRIS flumes carry MCERTS accreditation, so you can be confident that the data they collect is reliable and accurate.  In addition, our flumes are manufactured to very precise dimensions and tolerances, and can be supplied with a fully-integrated approach section, significantly reducing the likelihood of head gauging errors in the completed structure.

Our flumes are designed in accordance with BS/ISO 1438 and BS/ISO 4359 and will meet with all relevant regulatory discharge and MCERTS requirements.

All SIRIS products are compatible with our web-based data recording software, which allows quick and easy access to your data at any time – from any location.


Design & installation

We pride ourselves in offering a bespoke service to all of our clients. Our design and installation process ensures we provide you with a cost-effective solution tailored to suit your site’s individual requirements.When you first contact SIRIS, our friendly team will be on hand to take your enquiry and assess your needs. We know that every site has different requirements, so we’ll work closely with you to understand your individual needs.

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Compatibility with site systems

SIRIS flumes can be easily adapted to fit the size of the existing channel. We provide flumes for a range of flow rates in a variety of suitable materials, including stainless steel and GRP (fiberglass).

All SIRIS products can be used with our data monitoring software, Palette, however they are also compatible with your existing SCADA system. Our expert team is committed to working in partnership with our customers to meet their individual requirements and ensure our products fit seamlessly into each site.

Nick Richardson says...

“Our MCERTS-accredited venturi flumes are the universal choice for measuring in-flow to sewage treatment works. We offer a range of flumes in different sizes to suit a variety of applications – including smaller flumes which can be used for final effluent flow measurement or clean water discharge applications with low flow rates.”

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