By Gerhard Hope www.constructionweekonline.com
The proposed Doha Metro, an essential part of Qatar’s infrastructure for the 2022 World Cup, faces major scheduling challenges due to the tight timeframe, says Hyder Consulting regional rail director Geoff Leffek.
“The programme is very ambitious, and there is a clear deadline that nobody is going to be able to miss. You have got some very complex engineering, as you effectively have three very big networks.
“That is going to affect the way the work is procured almost certainly, because we have heard that they need to tender these contracts almost immediately. It is all coming up very quickly,” says Leffek.
Another major challenge is logistics, as “the vast majority of labour and material will need to be imported. I suspect that with the explicit support of the government, a lot of these issues will fall away, but some will not and will have to be dealt with.”
Leffek says “the biggest challenge is going to be in the CBD of Doha, in squeezing in all of the proposed metro into a densely-urbanised area.”
He says many of the multiple lines in the CBD will be tunneled, “sticking as I understand it pretty much to the boundaries of the roads above. It just adds another layer of complexity that, if you add the tight schedule, makes that, to my mind, the biggest challenge of that particular project.”
Leffek says the Dubai Metro is a good benchmark for the Doha Metro. “I am not a geologist, but I understand that Doha is the same as Dubai geologically.
“The issue they found here [in Dubai] was that the TBM (tunnel boring machine) tunnelling was very fast. It was almost too fast, as they were struggling to deliver the precast segments that make up the rings fast enough to feed the TBM.
“Thus I think the tunnelling itself, once the TBMs are in the ground and drilling, will probably be fairly straightforward. The big expense and the major complexity is getting the station boxes in, and to launch and receive those TBMs. This involves some very deep structures and multiple lines coming into some of the stations.”
Leffek adds that, “again, these are not new issues,” and points out that Qatar can draw on the Dubai Metro experience as well as other recent global projects such as the Gautrain in Johannesburg, South Africa.
He does add a note of caution, however: “We think of 2022 as being quite a long way away, but you are talking about a large number of very big projects, and all of them happening simultaneously.”
Leffek says he does not know “how developed those designs are [for Qatar’s rail projects]. DBI Design [an Australian engineering consultancy] is doing the concept design for the network at the moment. I have seen a lot of computer-generated drawings.”