At work today we got a chance to go walk in the underground tunnel that feeds the hydroelectric plant in Grand Falls. Access to the tunnel is pretty rare because it is usually flooded with rushing water from the Saint John River. The tunnel, dam and power house were built in the 1920's and work was completed in 1928.
Next summer will mark the 80th anniversary of the construction. It will also mark the year extensive rehabilitation work started at the dam. The project is expected to last several years. This summer construction was limited to the intake tunnel. The tunnel that passes underneath downtown Grand Falls is 3000ft long and lined with concrete (shaped in arch 24 ft high). We entered the tunnel at the power house and as we walked towards the intake valves near the dam, the fog increased to the point where it was kind of creepy. I took some pictures but they did not come out well. The picture below was not taken in the main section of the tunnel but rather near the power house where it turns into 4 different smaller tunnels that each feed a turbine. The Grand Falls hydro plant has four "Francis type" turbines.