Jizan Dam, Gravity dam in Jazan Region, Saudi Arabia

Jizan Dam, also known as Wadi Jizan Dam, is a gravity dam built from concrete in the Jazan Region of southwestern Saudi Arabia. It retains water flowing down from the surrounding mountains and shields the lowland areas from seasonal flooding.

The dam was built in the early 1970s to provide water to the growing population in southern Saudi Arabia. It was one of the first large water infrastructure projects completed in the Jazan Region.

Farmers in Wadi Jizan traditionally irrigated by basin flooding, building earth or stone barriers to hold rainwater on their fields; the torrents often swept these barriers away to the Red Sea. The dam replaced this with two diversion dams downstream that distribute water to 8,000 ha, where sorghum is grown alongside eucalyptus and tamarisk planted against desertification.

The dam sits about 16 km northeast of Abu Arish, reached from the road serving the wadi. Water released from the reservoir is distributed by two diversion dams downstream, so the channel below the dam can carry flow at times. The reservoir surface covers 1,409 hectares, and the spillway is 106 m long.

The dam's reservoir holds 51 million cubic metres of floodwater collected from five wadis. When it filled in the summer of 1970, seven small villages home to 267 residents were submerged; the Saudi government compensated them. The lake behind the dam covers 1,409 hectares.