Underground corrosion on rural distribution lines

ANCHOR-ROD corrosion on multigrounded distribution lines has been found to occur as a result of galvanic action between copper-covered ground electrodes and galvanized steel anchor rods connected to the system neutral through uninsulated guys. This galvanic corrosion, while not observed in a majority of soils, has caused premature failures or excessively rapid deterioration of anchor rods in certain low-resistivity soils in North and South Dakota and in some other states west of the Mississippi River. Direct currents associated with the most usual corrosion reaction are shown in Fig. 1.