WRcCSO Design & Installation

The patented and industry-recognised WRc Combined Storm Overflow that actively reduces environmental pollution being discharged from CSO spills.

Peter Henley is our expert in WRcCSO

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WRcCSO: Rethinking the CSO for the 21st Century

The design of combined sewer overflows (CSO) has largely remained the same for over 50 years, though more recently, additional storage and methods of screening solids have been added to traditional CSO designs. However, these screens require clearing either mechanically or by operatives. 

To address this, and to reduce pollution from CSO spills and the associated maintenance costs, we have developed an innovative, patented CSO design that reduces the floating solids presented to the screen by over 80%. This means that WRcCSO design actively reduces environmental pollution being discharged from CSO spills. 

      Practical, unique design

      The WRcCSO is a passive CSO solution that requires no power. It is designed to separate floating sewage litter (sanitary products, wipes, organic material etc.), and allow relatively clean effluent to be delivered to the CSO screens during high flows, reducing visible pollution to watercourses and beaches. 

      The material that is trapped by screens or spills out into the environment in traditional CSO design will instead be returned to the continuation flow for transport to the Wastewater Treatment Works (WwTW). As a further benefit of the twin chamber filter system, the required cleaning frequency of the screens is significantly reduced due to minimum litter being presented to the screens. 

          Minimises CSO environmental pollution

          Requires no power to be operational

          Manufactured from recycled materials

          Industry-recognised innovation

          • Reduction of debris on the screens, therefore there is no need for mechanically raked screen, reducing the capital and maintenance costs and improving reliability.
          • If the screen overtops in extreme events (as there is minimal floating litter in the spill chamber) then aesthetic pollution and cost of litter picking is reduced.
          • Monitoring of bypass spill gives early warning of imminent dry weather discharges before they occur.
          • CFD modelling shows litter separation of greater than 90% by optimising chamber sizes and relative weir heights.
          • Chambers can be retrofitted or installed as a new build.

          The WRcCSO is trademarked and improves the environmental impact of CSO spills whilst the water industry - WRc included - search for further solutions to address environmental pollution in the long term. WRc are not currently aware of an equivalent market competitor.

          Its game-changing design was shortlisted at both the Institute of Water SWA Innovation Awards 2021 and the Water Industry Awards, for which it was named a 2021 finalist in the category 'Wastewater Innovation Project of the Year' and for a second time in 2022.

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          Created by potrace 1.16, written by Peter Selinger 2001-2019
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          Peter Henley

          Principal Consultant (Pollution & Flooding)

          Peter has been in the waste water industry for over 30 years, specialising in sewerage operations and waste water issues. He has an extensive background in sewer flow surveys, pipeline condition assessment and inspection and rehabilitation. He works closely with the WRc Infrastructure team to deliver the condition assessment of live rising mains using innovative inspection techniques to determine remaining asset life.