Blackstaff River
The Blackstaff River is a watercourse that flows underneath the city of Belfast, Northern Ireland. It was formerly an overground river, but much of it was culverted and built over in the late 19th century. It rises on the slopes of Black Mountain and enters the River Lagan a short distance east of Belfast city centre. It was historically known as the Owenvarra, which comes from Irish Abhainn Bheara, meaning "river of the staffs". It is likely that this referred to a crossing made from oak beams, and that the "black" element referred to the colour of the beams.
The Blackstaff is known as a "Designated Watercourse" and is controlled and maintained by the Department of Agriculture and Rural Development's Rivers Agency. It has been cited as a main contributor to the high flood risk in central and low-lying areas of Belfast. In particular on 16 August 2008, a newly opened underpass carrying the M1 motorway onto the A12 Westlink controversially flooded to a depth of 20 feet (6.1 m) during heavy rain with water from the culverted Blackstaff and Clowney Rivers.
Coordinates: 54°34′51″N 5°57′48″W / 54.58074°N 5.96326°W
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