The challenge of securing future water supply and sanitation services for an increasing population requires continued efforts to satisfy the future needs. This paper focuses on water availability and sanitation services under growing population taking Gezira State, Sudan, as the case. Future projection of the population was predicted based on the 2.2% growth rate. Data on water sources, quantities and sanitation was collected from Gezira State Water Corporation and various health and educational reports. The results calculated that the population is increasing by 14% from 2008 to 2014. Water stands are the main source of water in Gezira and yields 84% of the available water. The current consumption rates are 22.5 and 55 Liter per capita per day for rural and urban population, respectively. There is a gab in rural water supply and is expected to increase rapidly by 2025. Sanitation coverage in the state is 80% in schools and 88% in health facilities. The study recommended construction of new water sources to satisfy the rural consumption.