The rate at which water is released can be controlled by a Vortex Flow Control (VFC). SDS supplies a range of VFCs and will specify the model that best meets the requirements of your installation.

How does it work?

Our Vortex Flow Control (VFC) is a self-activating device which induces a vortex motion in the water flow to control the rate that it’s allowed to enter downstream drainage systems. The energy in the water flow is harnessed to generate the vortex, so the device has no need for external energy supplies. Also, the Flow Control itself has no moving parts.

Compared to conventional flow controls such as orifice plates, throttle pipes and penstocks, the VFC has a superior hydraulic performance. The risk of blockage is minimised thanks to the outlet diameters that are up to 400% larger than conventional flow control devices.

Our VFCs have a unique head/flow characteristic with a distinctive ‘S’ shaped curve with high flush and kickback flow points. This helps to reduce storage volume requirements and ultimately lower project costs.

Our devices are made to all the relevant British Standards and typically use 10-gauge Grade 304 stainless steel. This material doesn’t corrode and is highly resistant to abrasion, so the life expectancy of each VFC is likely to exceed that of the system it’s installed into.

Units come equipped with a drain down/bypass mechanism which is remotely operated from ground level. In the unlikely event that there’s a blockage in the inlet or outlet of the VFC, the mechanism allows drain down of the system without the need for expensive overpumping or bypass penstocks and pipework. This differs from other makes of VFC, which can only bypass a blockage in the inlet.

Want to find out more about our full range of VFCs? Simply get in touch with a member of the team today.


Large outlet cross-sectional areas.
Resistant to blockages.

Drain down / bypass release mechanism.
Simple system drainage in the unlikely event of a blockage in either the inlet or outlet.

No moving parts.
Reliable operation and limited maintenance required.

No external energy requirements.

Unique head/flow arrangement.
Reduces storage volume requirements, thereby lowering project costs.

Manufactured using Grade 304 stainless steel.
Resistant to abrasion and corrosion, increasing product life expectancy.


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Discover how a VFC can benefit your development and get in touch now.