£150m Mogden upgrade to protect river
Local residents will soon see the first signs of preparatory work to improve Mogden Sewage Treatment Works in west London.
Aerial view of Mogden Sewage Treatment Works
Construction work will start in spring 2010 to significantly reduce the amount of storm sewage that overflows into the River Thames during heavy rainfall when the site becomes overloaded. But before then, vegetation will be cleared from the site ahead of the bird-nesting season.
The £150million project, due to be completed in 2013, will enable the site to treat more than 50 per cent more sewage than at present, so it can cope with heavy rainfall. This is one of five major sewage works upgrades starting in London this year.
Thames Water is investing a total of £650million to improve treatment standards and increase the volume of sewage treated at Mogden, Crossness, Beckton, Long Reach and Riverside sewage treatment works.
Steve Shine, Thames Water’s Chief Operating Officer, said:
"This work marks a fundamental step in improving the quality of London's iconic river.
"We inherited a Victorian sewerage system, which is struggling to cope with the demands of 21st century London. Since it was built, the capital's population has more than doubled, climate change is bringing less frequent but heavier rainfall and many green spaces have been concreted over, preventing natural drainage.
"Although our sewage works operate well under stable, dry weather conditions, in heavy rainfall excess flows pass through storm tanks, which provide a lower standard of treatment, and overflow into the tidal stretches of the River Thames - rather than having sewage back up on to the streets or even into people's homes.
"The improvements at Mogden Sewage Works, which currently serves 1.9 million Londoners, will enable the site to treat 50 per cent more sewage and allow for a six per cent population increase until 2021.
"As well as significantly reducing sewage discharges, these improvements will help reduce odour at the site, as the use of storm tanks during heavy rainfall will be reduced, and new and existing equipment will be covered over."
Before construction work gets under way in Spring 2010, parts of Mogden’s western embankment will be cleared, including the removal of trees and shrubs. When the project is completed, the embankment will be reshaped and the landscape enhanced for local wildlife. All this work will take place within the existing site boundary.
The work at Mogden forms part of Thames Water’s wider London Tideway Improvements programme. This is made up of three major schemes: the Lee Tunnel, Thames Tunnel and Sewage Works Upgrades.
In April 2010, Thames Water will start work on the £600million Lee Tunnel project, the first of the two tunnels, which will collectively capture an estimated 32 million tonnes of sewer overflows to the Thames each year. The four-mile tunnel will be as much as 75 metres deep, running from east London's Abbey Mills Pumping Station to Beckton Sewage Treatment Works. The seven-metre diameter tunnel - the width of three London buses - will capture sewage mixed with rainwater that would otherwise overflow into the River Lee at Abbey Mills following heavy rain.
The proposed Thames Tunnel, the bigger and more complex of the two tunnels, will run 20 miles from west London to east London, helping to prevent discharges from 34 Victorian overflow points along the River Thames. A planning application is expected to be submitted in 2011, with the tunnel due for completion in 2020.
