The river tunnel was cut through bedrock to divert the river from the head of the new engine shaft after water broke in. Constructed in 1846 and at a length of 120 meters, the project took four men one and a half years to complete. The intake for the great wheel is situated at the top end of the tunnel and in mid summer, the river has been known to dry up but in winter it consumes the full force of flash floods. Often inspected by the group, the roar can be deafening even when the river is low. |