Borough High Street

Borough High Street

About the Project

Deconstruct were awarded a Principle Contractor – Enabling Works package with Kings College London in late 2014 to demolish a number of dilapidated structures, strengthen and modernise a grade 2 listed building and then form an extensive basement across the entire site. Having been involved with the project for many years Deconstruct were well versed with the numerous challenges the project presented. These included a former World War Two access stair into the now disused City and South London underground tunnel located under Borough High Street. This along with the Northern Line which is within 5m of the proposed sheet pile line, removal of a whole host of dilapidated buildings which had not been occupied since the 1950’s and an extensive archeological dig for 5 months, plus the usual residency and stakeholder considerations.

On investigation the access stair was found to have been filled with concrete from around -3m to the City and South London underground level, we assume as some security protective measure taken by a long passed government. This presented design issues as the permanent structure then needed to be redesigned from a pile perspective to bridge this huge obstruction. Demolition of the structures and sheet piling was all delivered safely and on programme and archaeology started in ernest in June 2015. Most significant of the discoveries was a lead seal of Pope Innocent III dated between 1198 and 1216, over 1000 years old and is currently being checked to see if it can be linked to the sealing of the Magna Carta!

Archaeology completed safely and successfully in September and now the works are to create a new concrete basement and ground floor transfer deck across the site. A short film of the project will soon be released onto Youtube and linked to this case study.
The project includes:
  • Restricted Access to the site.
  • Demolition of 5 existing damaged buildings
  • Asbestos removal
  • Demolition of 5 existing damaged buildings
  • Provision of a permanent stabilisation frame only grade II listed building on the development site.
  • Sheet piling
  • Mass excavation twinned with Archaeological attendance
  • Reinforced Concrete basement box structure
  • Improved utility infrastructure

Project Challenges

The project, situated prominently on Borough High Street has a tunnel to which connected people from street level to the disused City and Western underground line, which was used as an air raid shelter during World War II. There were no records on this tunnel, therefore locating this anomaly on the site at the earliest opportunity possible would ensure the success of our delivery.

Similarly, there are live running LUL tube tunnels (Northern line) operating in front of the project, due diligence and care when working in this area are required to provide the assurances to 3rd parties and allow the smooth delivery of the scheme.