The Sultanate of Oman is located at the south east corner of the Arabian Peninsula. due to its geographical location at the arid and semi arid belt of the globe, it is classified as an arid country. Like most of the arid countries, it suffers from low rainfall and drought. In general, availability of water affected by natural factors, such as climatic factors, land topography, floods, high winds and rainfall intensity and by socio-economic development and human activities. Rainfall plays a very important role in the development, and distribution of cultivated lands, but the variability and extremes of rainfall can lead to serious problems such as soil erosion, drought and salinity intrusions. Both high intensity and less precipitation might cause serious problems to agricultural lands in arid countries. The quality of the available water resources for the different uses is also a challenge that faces some parts of the arid countries. In Oman, rainfall is the main source of natural recharge to all groundwater aquifers. The groundwater aquifers are the main sources of water in the country; it represents 92% of the total consumed water for agricultural sector. During 1998 and 2010, Oman was subjected to below average rainfall, with exceptional rainfall amount recorded during the two cyclones: Gonu and Phet which hit Muscat and the Sharqiyah regions. These events were exceptional and extremely high. This paper discusses the effects of low rainfall during the period between 1998 and 2010 on the depletion of groundwater resources and its effect on water availability. Long term data showed that there is a general trend of rainfall during the previous years. In most of the stations the amount was less than its annual average. As a result of this there was less recharge to groundwater aquifers which caused groundwater deterioration in both quantity and quality and land degradation. Evidences of this phenomenon are depletion of groundwater aquifers, dryness of aflaj and saline water intrusion in coastal areas.

The Sultanate of Oman is located at the south east corner of the Arabian Peninsula. due to its geographical location at the arid and semi arid belt of the globe, it is classified as an arid country. Like most of the arid countries, it suffers from low rainfall and drought. In general, availabilit...