Diligence team


Upgraded electricity supply to enable site expansion and increased processing of sewage in South London

Taken from Thames Water ‘Sewage Works Upgrades’ October 2013.

'We are carrying out a £220m upgrade at Crossness Sewage Treatment Works.

Work at Crossness will help prevent sewage entering the River Thames during heavy rainfall.

The improvements will enable the site to treat 44 per cent more sewage than it does now, significantly reducing the amount of storm sewage that overflows into the River Thames during heavy rainfall when the site becomes overloaded.'

What did Diligence contribute to this project?

Working for the Distribution Network Operator (DNO), Major Connections Directorate, we were able to provide the client with an increased high voltage electricity connection to power the existing and new plant, thus enabling the works to achieve the required increase in sewerage treatment.

Proud to take this project from feasibility through to construction and completion, this project had it all!  From liaison with stakeholders ranging from housing/land associations to schools; and having plenty of special engineering difficulties, including canal crossings and floating roads, this project was a significant achievement for all. 

With a complicated cable route (more than 50 per cent of which was through a residential area), modern route proving methods such as GPRS and construction using two horizontal directional drills were necessary.  Extensive land negotiations and work information packs also featured in the 2 and a half year electricity upgrade project.  

Nature also took part in the project (not just in the official conservation areas).  Japanese Knotweed required treatment and root barrier membranes throughout the cable route where the invasive plant had been identified.  In addition, we had reptiles, badger set, water voles and wasp spiders gracing us with their presence!  All logged and part of the project story!

With a plethora of specialists to work with including UXO (Unexploded Ordinance), Environmental Consultants, Environment Agency and other surveyors, we were able to give confidence to Housing and Commercial Associations, councils and highways who were actively encouraged to ‘drop in’ on the project.

Additional highlights include the development of relationships within the community near to the sewage treatment works, educating young people in both electricity and electrical infrastructure, retaining the recreational areas of the area and, of course, delivery of a successful project which featured in both the DNO and client’s internal magazines.  

Diligence went to work directly with Thames Water to provide the Process Management System integration of new & existing plant, plus additional Project Management for other projects within the Programme of the Upgrade.


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