Downtown LRT Tunnel Cost Estimates

Post date: Feb 12, 2013 3:14:43 PM

In December of 2012 the winning construction consortium was announced for the Confederation Line LRT project and a presentation made to City council. This included an update on construction costs which contained the following cost breakdown chart indicating that the cost to construct the tunnel and stations had been revised downwards from earlier estimates to 681m$

It is unclear from the presentation if the 'stations' referred to above are the 3 stations in the tunnel or all 13 of the LRT stations. If for the moment we assume it is only the 3 downtown underground stations and if we assume those are 50m$ each, then the cost for the tunnel itself would be in the order of 530m$. This is in the same range as is being quoted for the east end bridge under consideration.

The report goes on to say that the excavation of the tunnel and underground stations is estimated to involve the removal of 380,000m3 of rock and debris. By way of comparison, a Macdonald-Cartier bridge access tunnel to Nicholas street south of Laurier Ave could be estimated to involve a volume of rock = 1.7km (long) * 13m wide * 8m high = 150,000 m3 or less than half of what is involved in the LRT tunnel construction. Consequently we can expect that the cost of such a bridge access tunnel should be less than the cost of the LRT tunnel. By way of comparison, in 2008 the Ph1 study for an east end bridge crossing of the Ottawa R. (and associated access roads) was estimated to be around 500m$. In 2013 updated cost estimates pegged the cost of a bridge and associated access roads to be between 1.1B$ and 1.4B$.