The phenomenon of corrosion, a recurrent and costly deterioration mechanism, is present in metals since the beginning of ore extraction for its production. The corrosive process can be caused by humidity and direct contact with water. Grey water, reuse water, contains salts that may influence metal corrosion. The study of the corrosion by the accelerated test by accelerated electrochemical corrosion test in steel bars was carried out by immersion in saline water and grey water. The bars were emerged for a time of 8 hours on with a voltage of 15 Volts. The study of the evolution and the effects of the corrosion, on the bar, were followed by calculating the corrosion rate and by optical microscopy. The results show that grey water, with a low organic content, is a less aggressive electrolyte than saline water, indicating the possibility, safely, of using concrete structures to contain this residual water, on possible mechanisms to control the corrosive process.