Clearing the site
We consulted the community around the dismantling of the gasholders in October 2012. Wandsworth Council granted permission for the project in January 2013 and, since then, we the investigated the site to better understand it before starting the dismantling process. Since September 2013 our team has been at the gasholders site working on clearing the site.
There are four key elements to the work:
- Dismantling the gasholders
- Filling the voids left behind by the gasholders
- Demolishing existing buildings
- Environmentally improving the site
The gasholders have been cut into steel sections and removed from the site by road to be recycled where possible.
Holder 6 was the closest gasholder to Prince of Wales Drive and was dismantled first. This created the working space required to clear the rest of the site.
Holders 4, 5 and 6 were relatively similar in their design and construction and were dismantled in the same manner.
Dismantling holders No. 4, No. 5 & No. 6
- Holder fenced off for safety
- Removed any remaining sludge and water from the reservoir at the base of the holder
- Removed tank shell and, in the case of 5 and 6, removed columns
- Backfilled empty water reservoir
Holder 7 was carefully dismantled in sections from the roof downwards to account for its height and proximity to existing railway lines and a residential building.
Dismantling holder No. 7
- Removed 6,000 concrete blocks weighing down piston (complete)
- Installed roof top cranes
- Raised piston by blowing air into the gasholder
- Separated roof and lowered it onto piston
- Dismantled the holder section by section, lowering the cut pieces to the ground with the cranes
- Closer to ground level the remainder of the holder will be dismantled with an excavator and a special cutting attachment
Raising the piston, lowering the roof
Our contractors raised a piston that controlled the flow of gas out of the gasholder to its full height by pumping air into the gasholder. This was done by two air pumps known as ‘blowers’. The blowers were specially designed and commissioned by Coleman and Company for this job.
Once the piston was raised, the roof of the gasholder was cut and lowered onto the piston, creating a working platform.
The roof and piston was then lowered as more sections of the gasholder were cut away.