Two deepwater subsea production fields, Arnold and Oyster, started producing in 1998 in the
Ewing Bank Area of the Gulf of Mexico. The fields contain a total of four subsea wells with wet trees
and flowlines back to a fixed platform. Water depths range between 770 feet (235m) and 1,758 feet
(536m). During routine surveillance it was noted that some anodes on the well trees and flowlines had
excessive depletion. Since the field was undergoing expansion it was decided to supplement the
cathodic protection (CP) systems on all the assets to provide an additional 20 years life. This paper
describes the CP design and ROV-friendly methodologies used to install 19 anode arrays with 21
clamped tiebacks onto four flowlines and eight subsea components in 73 hours. Details on initial
system performance verification will also be presented.
Keywords: cathodic protection life extension, deepwater, subsea production system, ROV, wet tree,
jumper, manifold, flowline, anode pod, anode sled, aluminum anode