Kansas has a sub-humid continental climate with hot summers and cold winters, receiving an average annual precipitation of 31 inches. The major rivers are the Kansas, Arkansas, and Republican, with their tributaries forming a network of smaller streams. The state is not heavily dammed, and major reservoirs are primarily located in the eastern part of the state. The state's hydrology is dominated by the Ogallala Aquifer, which supplies water to agriculture, industry, and municipalities. Snowpack is generally low in Kansas due to its location in the Great Plains. Flash floods and droughts are the primary hydrologic hazards in the state, often resulting from intense rainfall events or prolonged periods of low precipitation.