Cathodic protection systems are systems which are designed to control the corrosion of a metal surface. Corrosion can destroy the integrity of your infrastructure. Patching the damaged area may seem the simplest and least expensive process of repair, but it may also be the least effective method for cathodic protection. Materials used for patching soon require repairs, and on a cyclical basis—each time growing more expensive. These repairs weaken the structure and may lead to the need for total replacement.