The Sewer Flow Regulator (SFR) or as it is also known, the Wastewater Flow Regulator, is an awarding-winning, patented, British innovation that has the ability to make a sewer networks smarter. Combined with a smart IoT sensor to tackle sewer flooding.

Compared to traditional penstock-type methods of flow control, the SFR offers several advantages. Fabricated off-site, each SFR is designed to be installed into an existing chamber, sitting on top of the benching and without disrupting the invert. The SFR components are also sized to fit through existing access chambers. Collectively these attributes substantially reduce disruption, civil costs, time of installation, and the carbon footprint of the deployment, plus post installation, the likelihood of blockages is minimal as the invert is unaltered.

The SFR is safe too. Operating using air-driven actuators, no electricity is required in the chamber. The design also includes a patented overflow weir to prevent surcharges that can be adjusted to set the spill point. Furthermore, once the body of the SFR is installed, the regulator element can be retracted for service from the surface in most locations without the need for confined space entry, cutting service costs.

sewer flow regulator installation

The SFR's lightweight construction makes it highly energy efficient too, enabling the SFR to be battery or solar-operated, making its whole life carbon footprint as close to net-zero as is practical. If mains power is available, the SFR includes a battery backup that permits its operation in the event of power failure

Sewer Flow Regulator Overview

  • Proven track record since 2018
  • Smart network compatible low cost and low carbon compared to re-laying sewers
  • Eliminates the need for new chambers – utilizes existing chambers and benching
  • Estimated to offer up to 80% cost savings over mains power operated penstock valve installations of equal size
  • Utilizing the existing invert means the SFR does not increase the risk of blockages
  • Designed to be installed through existing access hatches (< 55 cm)
  • Automated autonomous local control with remote telemetry reporting
  • Mains, battery, or solar operable enabling near net-zero deployments
  • Controllable using a wide range of smart network sensors
  • Safe air-operated actuators – eliminates the need for an electrical supply in the chamber
  • Controls housed in a small footprint roadside solar/mains control kiosk Includes a patented fully adjustable safety overflow weir
  • The lightweight, removable regulator element enables servicing from the surface without the need for confined space entry  

sewer flow schematic

The design mission with the SFR was to create a low carbon whole-of-life alternative, that was affordable and non-disruptive, fits easily into an existing network chamber. Additionally, it had to be easy to install, so any road closures would be hours rather than days or weeks. It also had to be installable in a live-flowing sewer without having to stop or bypass the flow and had to accommodate the differences between plastics, clay, and concrete inverts.

Crucially, the SRF was designed to be lightweight, hand carryable, and able to be installed without cranes. The consequence was it acquired a low inertial mass, slashing the energy required to operate to the point where today's SFR are operable from a small solar panel and battery.

For further information, download/view the sewer flow regulator leaflet here.

Vat GB591551821 Company Number 02906480 – 1994
Dun and Bradstreet, Number (581590544)
NATO Code Number (NCAGE KD520)
EORI Number GB591551821000

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Merlin Industrial Products @ 2023 Errors and Omissions Excepted


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