Thomson River Diversion Tunnel

The river flows around Stockriders Spur in a horseshoe bend. The tunnel was driven through the spur diverting the river and allowing the exposed river bed to be sluiced for alluvial gold.^{[1][2][3][4][5][6]}

The Thomson River Alluvial Gold and Tailings Recovery Company began construction of the tunnel in August 1911 and the tunnel was completed circa October 1912. The total length of the tunnel is about 220 metres (720 ft). The tunnel is one of around thirteen river diversions surviving from the Victorian gold rush.

The West Gippsland Catchment Management Authority believe that the tunnel may have interrupted the migration path of threatened native fish such as the Australian grayling. They are considering diverting the river back to its original course.^[7] This proposal is meeting some opposition.^[3]