The King Abdullah Canal is the largest irrigation canal system in Jordan and runs parallel to the east bank of the Jordan River. It was previously known as the East Ghor Main Canal and renamed in 1987 after Abdullah I of Jordan.
The main water source for the King Abdullah Canal (KAC) is the Yarmouk River and the Al-Mukhaibeh wells within the Yarmouk valley: farther south, additional water flows from Wadi el-Arab and from the Zarqa River, and its reservoir behind King Talal Dam. As a result of the 1994 Israel–Jordan peace treaty, some Yarmouk River water is also stored seasonally in Lake Tiberias, being conveyed through a pipe. The canal’s design capacity is 20 m3/second at the northern entrance of the Canal and 2.3 m3/second at its southern end. Water flows by gravity along its 110 km length, ranging in elevation from about 230 meters below sea level to almost 400 meters below. The Canal supplies water for irrigation and 90 million cubic meters/year of drinking water for Greater Amman through the Deir Allah-Amman carrier, which has been constructed in two phases in the mid-80s and in the early 2000s. The Zarqa River contains a mixture of treated wastewater and natural water flow, which influences the water quality downstream of the Zarqa River intake into the KAC.
The canal was designed in 1957 and was built in phases. Construction began in 1959, and the first section was completed in 1961. By 1966, the upstream portion to Wadi Zarqa was completed. The canal was then 70 km in length, and was subsequently extended three times between 1969 and 1987. The United States, through United States Agency for International Development (USAID) provided financing for the initial phase of project, after obtaining explicit assurances from the Jordanian government that Jordan would not withdraw more water from the Yarmouk than the amount allocated to it according to the Johnston Plan. It was also involved in later phases.