This paper reports the refurbishing of the 1200 A cathodic protection (CP) system on a 2-mile
(3200 m) long, 100–foot (30.48m) deep steel sheet piling wall after 30 years service. Included
are the diagnosis of the sheet piling by underwater ultrasonic measurements; the analysis of
the performance of the mixed metal oxides (MMO) anode array along the docks; and the
effects of cable defects that exposed the copper sheathing to aggressive environments on the
anodic side of the circuit and rapid deterioration. The paper also reports the performance of the
high current rectifiers; the replacement of the MMO anodes; the redesign of the anode
mountings; and, the wiring details of the anode connector cables and rectifier modifications.
The paper includes results of the tests of the CP current distribution in the wiring as well as the
return current from the protected structure to the rectifier. The status of the CP system
performance after the refurbishing is presented. The work included developing a numerical
model of the CP system as designed. The limitations of the original design are discussed in
view of all the metallic structures involved, other than the steel sheet pilings, serving in
environments other than the main dock sea front.
KEY WORDS Cathodic Protection system, Steel Sheet Piling Wall