Damour River

Damour River
The Damour river at Jisr el Qadi
Location
Country	Lebanon
Physical characteristics
Source
• location	Nabaa Al Safa, Nabeh Al Barouk
• elevation	1,950 m (6,400 ft)
Mouth
• location	Mediterranean Sea
• coordinates	33°42′21″N 35°26′22″E
Length	37.5 km (23.3 mi)
Discharge
• average	307,000 m3/a (0.344 cu ft/s)

The Damour River (Arabic: نهر الدامور, romanized: Nahr ad-Dāmūr) is a 38-kilometre (24 mi) coastal river in the Mount Lebanon Governorate in Lebanon, one of the country's seventeen perennial river systems. It rises in the Chouf Mountains and flows west and southwest to the Mediterranean Sea at the town of Damour, which takes its name from the river.

Course

The river's headwaters originate on and around the slopes of Jabal el-Barouk, a 1,943-meter peak that is also home to the Al Shouf Cedar Nature Reserve, site of some of Lebanon's largest and oldest Cedars of Lebanon. Two springs Nabaa al-Safa and Nabaa al-Barouk, feed the river at an elevation of about 1948m (6,391 ft). From there the river flows west through the Jisr al-Qadi valley, where it is joined by streams draining the Chouf mountains before reaching the coastal plain entering the Mediterranean just south of the town of Darmour.

The Darmour river basin cover an area of approximately 290 km² (112 sq mi), according to hydrological studies published in the 2000s and 2010s, though a 2025 a water management assessment gives a figure of around 305 km² The basin is bordered by the Beirut river basin to the north, the Litani River basin along the Mount Lebanon water divide to the east, and to the Awali River basin to the south.

Hydrology and geology

The Damour basin's geology is dominated by Jurassic limestone and dolomite surrounded by Cretaceous, Tertiary and Quaternary deposits, karstic formations make about 27 percent of the watershed. Thick karstic limestone forms the basin major aquifer system, with faults linking the mountains aquifers to those of the coastal plain, the Darmour coastal aquifer is a significant source of irrigation and municipal water with hydrochemical and isotopic studies showing that up to 30% of pumped groundwater is reached in the high mountains of the upper basin.

Snowmelt accruing between March and May is a significant source of the river's flow. The average discharge at the river mouth has been estimated at approximately 307,000 m³ per year. Hydrological modelling using modified Soil and Water Assessment Tool project, under the RCP 4.5 emissions scenario for 2032 a 2008 baseline a 20 percent decline in precipitation on the coastal portion of the basin and a 30 percent decline in the mountainous portion, with mean monthly water yield falling by roughly by 24 percent and the sharpest reduction occurring in January. Broader Mediterranean-wide assessments similarly project continued declines in regional precipitation over the coming decades.

Water quality

A study of recreational stretch of the river, sampled annually between 2005 and 2009, classified overall water quality as "good" using the water quality index, though quality declined to "medium" at the estuary, reflecting cumulative impacts from upstream villages and recreational use. Fecal and total coliform bacteria counts exceeded European Economic Community bathing water guidelines throughout the studied section, indicating a public health risk to swimmers. A separate comparative study of four major Lebanese rivers the Damour, Ibrahim, Kadisha, and Orontes, sampled over 2010–2011, found that the Damour and Orontes had the lowest rate of pollution among the four, with springs at their sources showing good water quality largely free of severe contamination..

Water management

Two diversion dams on the river feed local irrigation networks. The lower dam diverts approximately 1,100 m³/h and the upper dam approximately 650 m³/h. The river and it coastal aquifer support banana cultivation and other agriculture across the coastal plain, as well as tourism in and around Damour. A 2025 integrated management plan developed under the GEF UNEP/MAP MedProgramme, led by the Global Water Partnership-Mediterranean aims to coordinate management of the basin's land, water, delta, estuary and coastal ecosystems. It notes that overuse of river water upstream users has contributed to downstream water shortages, particularly in the summer, and identifies the Damour coastal aquifer as a significant source for the Beirut water supply.

Etymology

The river and the town of Darmour at its mouth, take their name from the Phoenician god Damoros or Tamyrus..

History

Adjacent to an iron bridge at the mouth of the Damour River, possibly built in the 19th century, lie the stone foundations of an earlier structure, including a masonry abutment on the left bank, foundation traces on the right bank and the remains of what may have been a pier on a small mid-river island. Historical evidence points to medieval bridge built in 1291, during the reign of the Mamluk sultan Al-Ashraf Khalil following the conquest of Sidon and Beirut, and rebuilt in 1340 and 1344. It may have been destroyed by heavy rain and flooding in 1503–1504.

During the Syria-Lebanon Campaign of WWII, the Battle of Darmour (5–9 July 1941) turned on control of the river crossing. The Wadi Damour, carrying the river was the last major natural obstacle facing Australian forces of the 7th division before Beirut, and on the night of July 5th troops of the 21st Brigade crossed the river at two points to out flank Vichy French positions holding the town.