The work presented was carried out at the Casa Grande Company in the area of the Garrapon reservoir, with the information of volumes consumed during the period 2013-2016. This work analyzes and calculates the water balance presented by the reservoir, and then evaluates the efficiency and efficient management of the water resource stored in the reservoir for the irrigation of fields under its influence, to adequately and timely satisfy the water requirements that the cultivated sugar cane needs. The Casa Grande Company controls only the in and out of the waters of the Garrapon Reservoir, but doesn’t take into account additional parameters such as evaporation and precipitation, which must be considered in the total balance sheet. The values obtained from the water balance of the Garrapon Reservoir are determining values for an adequate irrigation program in the future. For the water bala...