Project start: October 2012
Project finish: March 2012
Location: Maiden Lane Reservoir, London, NW5 1JE
Reservoir maintenance works as part of Thames Water Reservoir Maintenance Agreement.
Maiden Lane Reservoir is situated on Dartmouth Park Hill in the London Borough of Islington in Central London. The reservoir is a brick-built covered service reservoir which was completed in 1855. It is composed of two separate structures, known as the north (Cell A) and south (Cell B) compartments, which together have a capacity of 68,200 m³. The depth when full is about 6.7m.
The challenges on this project included working on a 150 plus year old structure and also on a Site of Importance for Nature Conservation (SINC). We were also working next to a public park and residential area which meant noise and working hours were an issue.
The works included the following:
1) Installed new HDPE roof membrane along with geotextile underlay and cuspated drainage sheet on the reservoir roof (5500m²).
2) Installed new MDPE roof drainage outlet and collector pipes and connect them to existing drainage chamber. Diamond drilled holes through perimeter walls for drainage pipes.
3) Removed, transported and stored soils temporarily in agreed method to enable roof membrane installation and backfill excavated soil on completion of membrane installation.
4) Removed / diverted existing cabling, ducting and sampling pipes from reservoir roof and re-install them on completion of roof refurbishment work.
5) Rotovated and grass seed to the agreed seed mix.
6) Provided assistance during reservoir internal inspection (including CP2 confined space entry).
We also repointed the parapet walling on Cell A & B. And installed a new ladder (approx. 9.9m high) in the Southern Central Cistern. Design / fabrication. Finally we chlorinated and returned Cell A to service following completion.