Chambers Wharf
I wanted to do a blog about the issues that we’ve discovered on site, but then I realised that I haven’t actually written a blog to orientate people to the site. Therefore I’ll do two smaller blogs. I’m not planning on orientating people to the tunnel in general, unless people have specific questions, as it’s covered on the internet here http://www.tideway.london/the-tunnel/construction-sites/.
This blog will briefly introduce the site, and the following one will look at some of the issues in detail. This has the added benefit of not boring everyone too much, and boosting my blog numbers so that I can compete with Holtham and Nelson for the ‘Most Prolific Blogger Prize’.
I am attached to CVB JV (Costain, Vinci G.P. and Bachy Soletanche) who are delivering the Eastern section of the Thames Tideway Tunnel (TTT). I will be based on the main drive site located at Chambers Wharf and my first task is to coordinate the initial site works, to establish site and the temporary (until 2023) office and welfare facilities. The initial works will include utility diversions, demolition of structures including an existing substation, installation of welfare facilities (to be delivered by barge), installation of the cofferdam and demolition of the existing RC jetty. Once these works are underway we’ll have time to focus on the shaft excavation for the TBM.
Within the site boundary there are 2 other Principal Contractors currently working. One to clear the site following demolition works conducted in 2009, and the other to divert existing services and to install services for the Tunnel Boring Machine (TBM).
The phasing and integration of the different work packages works well on paper (figures 1 and 2 show how it is meant to work), but having attended two integration meetings it is clear that the programme appears to be moving towards one long critical path. The other PCs packages have been delayed by asbestos, noise and vibration complaints, and barge issues, and is starting to impact on the phasing of our works. I will expand on these site issues in my next blog. In the meantime, if our works are delayed due to other PCs failings I expect there will be some interesting contractual issues, but I will have to wait until the Contract Execution Plan is released before I can comment on this in more detail.
As the plan stands we will be establishing our own site on 21 Mar 16. Further than this, our progress is dependant entirely on the neighbouring contractors spoil removal, but with a good wind we will soon be starting works to the hoarding which is a not insignificant 3.6 – 5m structure supported by kentledge or posts, and excavating for the foundations for the modular office building.
The office modules are due to start arriving by barge on 21 Apr 16 and will be offloaded by a 100T crane, and then lifted in to place by a 200T crane. Simples!
Figure 1. Site Integration w/c 21 Mar 16
Figure 2. Site Integration w/c 18 Apr 16
Holdfast Training Services Trial Blog 
Looks nice and congested. I like the fact that the plan makes handover of PC responsibilities clear. Are those expensive riverside residences on the left of your site? Do you have any plans of the site as it will be when you have a shaft on it? Presumably there will be more than just the two mobile cranes at some pooint?
Richard, I’m planning on covering the longer term works in a later blog, but essentially we demolish the existing jetty and build a new one further out so that the barges are no longer affected by tide timings. This means the excavation for the tunnel can be 24 hours. The shaft is in the NE corner of the site. There will be a small crane for offloading materials on the new jetty but the spoil from the TBM will loaded onto the barge by a conveyor. The shaft will be enclosed by an “Acoustic Shed” so that tunnelling can be conducted 24hrs a day.