Combined Sewer Overflows (CSO’s)
The majority of the UK Water Companies that manage wastewater operate an extensive sewer network which conveys both foul and surface water flows. This combined sewer system is often unable to cope with periods of high rainfall and spills to water courses via controlled Combined Sewer Overflow points.
In order to comply with, and meet the requirements of, the Environment Agency’s Asset Management Programme it has been necessary for the Water Companies to undertake a programme of CSO upgrades.
General requirements of the CSO upgrade programme are provision of 6mm 2d screening, ensuring passage of ‘Formula A’ flows prior to spill (maximum flow to treatment is determined by Formula A) and overflow monitoring and reporting.
DSI has been involved in over twenty CSO schemes over recent years and working closely with our Clients we have successfully delivered the following;
♦ Modelling and analysis of sewer system to identify possible solutions
♦ Innovative solutions including retrofitted, new and re-located chambers
♦ Installation of new 6mm 2 dimensional screens (mechanically operated and static options)
♦ New overflow monitoring and telemetry systems
♦ Hydraulic upgrades to satisfy revised consent criteria and ensure no detriment to existing levels of service
Despite extremely tight programmes we have achieved repeated success in meeting compliance dates and helping to obtain EA compliance certification for all schemes.
