Halting sewage litter from Combined Sewage Overflows

At a time when the media constantly shows footage of unsavoury sewage litter from Combined Sewage Overflows (CSOs) that pollute rivers and beaches, Fluid Motion Solutions, part of the global NOV group (National Oilwell Varco) are backing a new patented product, NORAG, which has been designed to prevent such occurrences.

Developed by Samatrix, NORAG is a maintenance-free solution that has no moving parts and requires no electrical power. Using the Venturi effect, NORAG continuously draws off sewage debris from within the CSO screening chamber during storm conditions and high flows, allowing the screen to operate (as designed) for longer. This ultimately reduces the frequency of unconsented spills that result in sewage litter being sent to water courses.

Fabricated from 316-grade stainless steel, NORAG has a product lifespan of around 30 years. It can be adapted to fit into most existing CSO’s without the requirement for costly excavations or structural modifications. NORAG simply returns any drawn off debris back into the main flow for disposal at the treatment works.

NORAG inventor and Samatrix MD, Samuel Munn commented: “The industry knows that due to ever increasing and more extreme storm events, existing screening systems alone can’t prevent the influent from thickening; resulting in inevitable screen blinding, eventually sending all this very unpleasant waste over the blocked screen into rivers and on to beaches. These measures are no match for today’s wastewater challenges.  They are, unfortunately, doomed to fail.”

Neil Davies, Director of Industrial Business Development for NOV’s Fluid Motion Solutions, added: “Rather than simply trying to improve the screen in a CSO, which others have tried, but not resolved, we see the huge benefits in how Norag tackles the problem of sewage litter pollution. It is a completely different approach; making CSOs work far more efficiently and effectively.  This is a golden opportunity for the water industry to stop ghastly sewage-related debris from being seen in rivers and on beaches.”