Straight, clean holes with jet grouting at Niagara, Canada
Niagara Falls is one of the biggest tourist attractions in North America. Visitor pressure is heavy in the town of Niagara, next to the mighty Horseshoe Falls in Canada. It has become necessary to increase the hydroelectric power output there to meet demand for electricity.
The construction of an 11 km-long tunnel to add another turbine at the dam began in 2007. The tunnel measures 15 meters in diameter. It starts above the falls and has its outlet below them. The project is large and complex, and the safety requirements have been strict.
Geo Foundation has used Wassara water-powered hammers in connection with jet grouting at the inlet and outlet. They are drilling 400 67 m-deep holes to reinforce the ground around the tunnel opening. Geo Foundation chose Wassara's waterpowered down-the-hole hammer because of its ability to drill in almost any type of ground conditions, and because it is very well suited for use in water-bearing ground.
Another of its advantages is that the boreholes are straight and clean, which is a requirement for the geophysical testing needed to determine how much grouting the ground can tolerate. Wassara's precise and safe technology has once again demonstrated its advantages in an advanced project.