One of numerous dams along the wadis running westward into the Jordan River, the King Talal Dam forms a large reservoir in Wadi Zarqa (“the Blue River”) – the country’s second-largest river and known in the Bible as the Jabbok. The dam was constructed in the 1970s and raised in the 1980s to increase the capacity of the reservoir.
The river’s large flow originates partly from rainwater and runoff and partly from the groundwater flowing in from far to the east. The steep banks of the wadi have undergone much ecological damage over the millennia that humans have lived there; but they are still home to many plant and animal species, including both resident and migratory birds.
As its watershed includes Amman and many of the other most built-up areas of Jordan, the waters of the river are quite polluted. Despite this, the dam provides the possibility to use the river’s water for irrigation as well as power generation – but the water quality of the river is still a major issue. The dam currently plays little role in protecting the watershed or ecosystems of Wadi Zarqa, but the irrigation water drawn from it enables many thousands of people in the Jordan Valley to make a living through agriculture and provides renewable hydroelectric energy.