Loch Glascarnoch near Garve supplies water to Mossford power station.
A road that used to link Inverness and Ullapool, two bridges and part of a telegraph pole have been visible and were photographed by Calum Maclean.
Glascarnoch and its dam form part of energy giant SSE's Conon hydro electric scheme, which involves six dams and seven power stations.
The dams and power plants were built in stages between the 1940s and 1960s.
A new road to Ullapool was built to replace the one lost under Loch Glascarnoch.
SSE said the water level of the loch had been lowered for operational reasons.
A spokesperson said: "As we head into the winter we've pulled the level down because the rain we usually get in October and November can raise the levels up by as much as one metre a day."
Water levels at a loch created in the 1950s have dropped low enough to reveal structures usually hidden underwater.