This study reviews the geology and history of the Minnelusa reservoir of Timber Creek field and focuses on CO2 Water-Alternating-Gas (WAG) flooding development strategies after more than 50 years of primary and secondary recovery. To forecast the performance of several CO 2 WAG scenarios in Timber Creek, a seven-layer full-field static model has been developed. The model consists of Minnelusa A, B, C and D sandstones, and each of them is separated by a layer of dolomite. The history matching process starts from December 1962 to September 2015 using Eclipse compositional simulator (E300). Three CO2 WAG flooding scenarios were simulated and compared with a base case, water flooding scenario. Based on an economic analysis, out of the three CO2 flooding cases considered (WAG ratios of 1:1, 2:1 and a tapered WAG) the CO2 flooding with a WAG ratio of 2:1 will have the best economic performance.