To augment the power supply for the expanding operation, electricity was transmitted from hydro-electric plants at Nugget Creek (near Mendenhall Glacier) and Sheep Creek (across Gastineau Channel at Thane). Energy voltage was increased to facilitate long distance transmission and was converted from 23,000 volts back to 2,400 volts in this small concrete structure next to the power plant. The electricity could then be distributed to the mining, milling and support facilities. The transformer room is still in place and the traditional red paint with green trim that was used throughout the complex is replicated on the building.