Yarmuk River

Overview

The Yarmuk River is the principal eastern tributary of the Jordan River and Jordan's largest river. Its upper tributaries drain Bashan; its lower course joins the Jordan River from the east. The confluence makes the Yarmuk a major part of the regional water system shared by Israel and Jordan. Within descriptions of the historic Land of Israel, the river ranks second only to the Jordan in water volume and third in length, after the Jordan and Nahal Paran. Its water supports irrigation, enters the Jordan system and figures in arrangements between the two countries.

The origin and meaning of the name Yarmuk are unknown. Names recorded over time reflect the river's long place in regional geography: Pliny the Elder wrote Hieromices, a form also found on coins of Gadara; the Peutinger Map gives Heromicas. Byzantine writers from the eighth through eleventh centuries used Hiermochthas or Thos. In Arabic, the lower course is Nahr al-Yarmuk and the middle course is Shariʿat al-Munadira.

Geography

Maps identify the upper course with Wadi Zaydi, the Yarmuk's longest intermittent feeder. It rises on Mount Bashan and carries water throughout the year in the mountains. Across the Bashan tableland it passes Bozrah and Edrei. Beyond Edrei the course continues as Wadi al-Madan, which holds water for most or all of the year. Wadi al-Dhahab descends from Bashan and joins it northwest of Edrei. Nearby, Wadi al-Bajja adds abundant perennial water from a lake and springs at Muzayib. Below that junction, the Yarmuk flows year-round, even during drought.

Below the mouth of Wadi al-Bajja, the river cuts a deep gorge beneath the surrounding plateau. Tributaries descend into it through ravines, creating waterfalls that become more numerous during heavy rain. Streams from Bashan and the land south of the river enlarge its flow; runoff from their drainage areas also produces floods. The gorge and its steep sides have shaped both movement along the valley and schemes to divert its water for irrigation.

Ancient and biblical history

Neolithic inhabitants of the Yarmuk Valley adjoining the lake practiced agriculture, an early indication of the valley's value as a source of water and cultivable land. In the ninth century BCE, Damascus ruled Hauran and Bashan as far as the Yarmuk. The river thus appears in accounts of the region as both a watercourse and a geographic limit. Later Greek, Latin and Byzantine renderings of its name attest to continued recognition of the river across successive periods of rule.

In 636, the Battle of Yarmuk ended Byzantine control across much of the region and opened the way for Arab rule. The river gorge mattered to the fighting: ravines hindered retreating Byzantine troops, while a desert wind blowing from the south blinded them. The defeat altered the political order well beyond the valley, including the lands around Damascus and the Jordan River.

Jewish history

The Mishnah contains the first Hebrew mention of the Yarmuk. In its discussion of water used for ritual sprinkling, it classifies the waters of the Jordan and Yarmuk as mixed waters unsuitable for that purpose. Estori ha-Parhi identified the mixed waters with those of Hammat-Gader, which empty into the Yarmuk. His reading treats that inflow and the course below it as the river meant by the Mishnah.

The Babylonian Talmud and Midrash Tehillim use Yarmuk for the entire river. They enumerate it among four rivers marking the border of the historic Land of Israel. These texts give the river a place in Jewish descriptions of the land as well as in accounts of its physical geography.

Modern history

A railway laid through the Yarmuk Valley in 1908 linked Haifa with the Hejaz railway. The connection to Haifa was cut in 1948. The river's name also acquired a military association during the 1948 Arab–Israeli War. In 1947, Fawzi al-Kaukji named a force of his Arab Liberation Army the Army of the Yarmuk in memory of the seventh-century battle. That force was defeated and dispersed near Mishmar ha-Emek in 1948.

Water development made the river a focus of regional diplomacy. U.S. envoy Eric Johnston conducted nearly three years of negotiations over the Jordan and Yarmuk systems after Israel and Arab governments submitted separate allocation proposals. A regional plan proposed an upper Yarmuk dam able to impound 300 million cubic meters of regular flow and generate 150 million kilowatt-hours of electricity annually. Because a dam could not economically capture every flood, the plan also proposed storing an estimated annual average of 80 million cubic meters of Yarmuk floodwater in the Sea of Galilee for Jordan's account.

The allocation proposal assigned Jordan 377 million cubic meters of Yarmuk water and Israel 25 million. Under the Johnston Plan, Yarmuk water could meet about 85 percent of Jordan's needs. Jordan was already drawing substantial water from the Jordan–Yarmuk system under its Yarmuk Plan before Israel began drawing its share. Arab governments nevertheless sought to prevent Israel from doing so. Israel's defined allocation remained part of the regional proposal while Jordan used the same system. One water-policy assessment estimated that 100–150 million cubic meters of Yarmuk water flowed through the Jordan River to the Dead Sea unused.

Security

During the Syrian civil war, the Khalid ibn al-Walid Army, a proxy of the Islamic State, controlled the Yarmuk basin. Control of the basin gave the armed group a position near the river corridor and the southern edge of Bashan. The episode placed a historic watercourse within a wider struggle for territory and security.

Present day

The water annex to the Israel–Jordan peace treaty sets seasonal Yarmuk allocations. During the summer period, Israel pumps 12 million cubic meters and Jordan receives the remaining flow. In winter, Israel pumps 13 million cubic meters, and Jordan permits it to pump an additional 20 million in exchange for a summer transfer of 20 million cubic meters from the Jordan River. Israel also pumps Yarmuk water into the Sea of Galilee.

The treaty requires mutual agreement before either country artificially changes the course of the Jordan or Yarmuk rivers. It provides for cooperation on water quality, storage and the exchange of water data. Those provisions reflect the continuing importance of the Yarmuk's flow to both countries and the practical need to manage their connected river systems together.