The present invention provides a permanent and cost-effective composite electrode for electrolytically producing alkaline water, comprising an electrode core made of steel, a filler densely packed around the electrode core, said filler capable of creating a mildly aqueous and alkaline environment to motivate formation of a layer of magnetite over a surface of the electrode core, and a housing enclosing the filler, said housing having a pore size selected such that very low permeation of gas and liquid takes place. The invention also provides an apparatus comprising the composite electrode, and the use of the alkaline water produced by the apparatus of the invention. According to the invention, no additional undesired side products, such as toxic chlorine gas and other pollutants, are produced and discharged to the environment.