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Reference list (excerpt)

Tender, final and construction design as well as geotechnical supervision on site for the 10.4-km long pressure tunnel with intake and outlet structures.

The Tunnel conveys 500 m³/s from the upper reaches of the Niagara River to the powerhouse just below Niagara Falls passing underneath the city of Niagara Falls and underneath existing diversion tunnels.The tunnel is excavated by a hard rock TBM featuring a diameter of 14.4 m. During excavation, an initial lining will be installed. The final lining, with a thickness of up to 0.7 m, will consist of non-reinforced concrete. For the structure to sustain operating pressures of up to 15 bar, the final lining will be pre-tensioned by interface grouting.