There are 33 permanent and seasonal rivers in the province that are used for drinking and agricultural purposes. The total surface and ground water potential is 4850 million m³. the most important rivers includes Seimareh, Godar Khosh, Konjan Cham, Gavi, Changooleh, and Meymeh. The total annual rainfall is 8590 million m³. The distribution of precipitation includes about 50 percent of annual total in the winter,29 % in the fall,20 % in the spring, and very little during summer (1 %).