Lough Neagh EUR-34

Riparian Nation(s) UK
Surface Area 385 km2 Mean Depth 8.9 m Volume 3.45 km3
Shoreline 125 km Catchment Area 4453 km2 Residence Time 1.24 yr
Frozen Period None Mixing Type Homogeneous Morphogenesis/Dam
Related Info/Site


The largest area of fresh water in the British Isles. Lough Neagh, is an eutrophic lake 385 km2 in area, mean depth 8.9 m, and is located centrally in the province of Northern Ireland. The lake is so shallow that the water remains always muddy due to wave and turbulent mixing by strong winds. The lake does not stratify in summer and very rarely freezes in winter. Transparency varies between 1.0-2.0 m due to the brown water and large phytoplankton crops which are dominated by blue-green algae and diatoms. It is an important eel and salmon fishery, provides the main water supply for the city of Belfast and the lake-bed is worked for sand and gravel (Q, 10).

Photo of Lough Neagh
Photo: A. Kurata