$1.6 billion

Sector: Energy

Location: Niagara Falls, Ontario

Key Players: Strabag AG (design-build contactor); ILF Beratende Ingenieure (tunnel designer); Morrison Hershfield (designing above-ground work); Dufferin Construction (major subcontractors); The Robbins Company (tunnel boring machine supplier);Hatch in association with Hatch Mott MacDonald (owner’s representative); Rowa (TBM backup equipment); Sunny Corner Enterprises (electrical)

Owner: Ontario Power Generation (OPG) Financing: Public – OPG has a design-build contract with Strabag AG. This project was listed at $950 million on last year’s list, but the cost has increased by 62 per cent. It remains to be seen who will swallow that extra cost, the provincial body or the design-builder.

Status: Scheduled for completion in 2013.

Project Details: Ontario Power Generation is working on a third tunnel beneath Niagara Falls to generate additional power at its Sir Adam Beck Power generating stations on the Niagara River. Existing twin tunnels and a hydro canal currently supply approximately 1,800 m3 of water per second to the Sir Adam Beck Generating Stations. The new tunnel will divert an additional 500 m3 of water per second and, with an internal diameter of 12.7 metres and a length of 10.2 kilometres, is expected to be one of the largest tunnels built in North America. But Big Becky, the massive boring machine that’s digging that largest tunnel, has run into some unforeseen geology and is behind schedule. OPG told CBC news that the project will be late and over budget, but the details are still under review.