River Lagan

River Lagan
River Lagan at Lanyon Place, Belfast
Map of the Lagan River drainage basin
Native nameAbhainn an Lagáin (Irish)
Location
Sovereign StateUnited Kingdom
Constituent CountryNorthern Ireland
CountiesAntrim, Down
Physical characteristics
SourceSlieve Croob
 • locationNorthern Ireland
 • coordinates54°20′24″N 5°58′23″W / 54.340°N 5.973°W / 54.340; -5.973
 • elevation119 m (390 ft)
MouthBelfast Lough
 • coordinates
54°41′28″N 5°47′06″W / 54.691°N 5.785°W / 54.691; -5.785
Length86 km (53 mi)
Basin size609 km2 (235 sq mi)
Basin features
Tributaries 
 • leftRiver Farset, Blackstaff River
 • rightCarryduff 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]

  1. ^ "Guide to Moira Station – Department of the Environment" (PDF). Doeni.gov.uk. Archived from the original (PDF) on 25 October 2013. Retrieved 27 November 2013.
  2. ^ Ordnance Survey of Ireland: Rivers and their Catchment Basins 1958 (Table of Reference)
  3. ^ "River Lagan". Banbridge District Council. Archived from the original on 24 April 2009. Retrieved 28 February 2009.
  4. ^ "River Lagan Impoundment". Agri-Food and Biosciences Institute. Archived from the original on 21 May 2009. Retrieved 28 February 2009.
  5. ^ "Restoration of a self-sustaining Atlantic salmon population to the river Lagan, Belfast, Northern Ireland". Central Fisheries Board. Archived from the original on 24 April 2009. Retrieved 28 February 2009.