The incorporation of the smart technologies in injection wells has not been widely considered before this work, hence the originality.The world’s demand for oil product is increasing gradually and lack of new significant discoveries has made it imperative to look for secondary processes and better technology that will help increase oil production. One of the secondary recovery mechanism used all over the world is waterflooding. Waterflooding is used in nearly all the fields in the world, it is used after natural depletion, and it’s used for pressure maintenance and volumetric sweep of the reservoir. Smart well technology is another technology that is assisting in increasing oil production, it’s a non-convectional well with downhole instrumentation (sensors, valves and inflow control devices) installed on the production or injection tubing. This work presents a methodology where waterflooding is been controlled by smart injector well technology to help optimize or increase the net present value of the Field. The optimization procedure was done on three different case studies of commingled reservoir having different layer characteristics; it involves vertical smart injector well and production well penetrating fully through the commingled reservoir. A set-up optimization procedure was applied, were rate allocation method was used at each zone of the smart injector well. In this research, the right rate allocation to each zone that gives the maximum Oil recovery or highest Net Present Value gives the answer to the Waterflood Optimization setback. The smart injector well use in this research has Inflow control Valves which can automatically open and close in order to meet certain reservoir or production requirements. Installing Smart Completion on the injector well gives an opportunity to control all cases of early water breakthrough and reduce water recycling in some reservoir layers; which will ultimately lead to an increase of 2% - 8% in the Net Present Value and 6% - 9% Cumulative Production of from the field. This Technology is highly recommended for Niger Delta fields to improve recovery and delay water