River Lagan | |
---|---|
River Lagan at Lanyon Place, Belfast | |
![]() Map of the Lagan River drainage basin | |
Native name | Abhainn an Lagáin (Irish) |
Location | |
Sovereign State | United Kingdom |
Constituent Country | Northern Ireland |
Counties | Antrim, Down |
Physical characteristics | |
Source | Slieve Croob |
• location | Northern Ireland |
• coordinates | 54°20′24″N 5°58′23″W / 54.340°N 5.973°W |
• elevation | 119 m (390 ft) |
Mouth | Belfast Lough |
• coordinates | 54°41′28″N 5°47′06″W / 54.691°N 5.785°W |
Length | 86 km (53 mi) |
Basin size | 609 km2 (235 sq mi) |
Basin features | |
Tributaries | |
• left | River Farset, Blackstaff River |
• right | Carryduff River, Ravernet River |
The River Lagan (from Irish Abhainn an Lagáin 'river of the low-lying district'; Ulster Scots: Lagan Wattèr)[1] is a major river in Northern Ireland which runs 53.5 mi (86.1 km)[2] from the Slieve Croob mountain in County Down to Belfast where it enters Belfast Lough, an inlet of the Irish Sea. The Lagan forms much of the border between County Antrim and County Down in the east of Ulster. It rises as a tiny, fast-moving stream near to the summit of Slieve Croob; Transmitter Road runs nearby. It runs to Belfast through Dromara, Donaghcloney and Dromore. On the lower slopes of the mountain, it combines with a branch from Legananny Mountain, just opposite Slieve Croob. The river then turns east to Magheralin into a broad plain between the plateaus of Antrim and Down.[3]
The river drains approximately 609 square km of agricultural land and flows to the Stranmillis Weir, from which point on it is estuarine.[4] The catchment consists mainly of enriched agricultural grassland in the upper parts, with a lower section draining urban Belfast and Lisburn. There is one significant tributary, the Ravernet River, and there are several minor tributaries, including the Carryduff River, the River Farset and the Blackstaff River. Water quality is generally fair, though there are localised problems and occasional pollution incidents, mainly due to effluent from farms. Work is proceeding to restore a self-sustaining population of Atlantic salmon to the river.[5]