尼亚加拉大瀑布有多高？水流有多快？

Niagara Falls Geology Facts & Figures (History & Future)                                                                                       

How High is the Falls? How fast is the water?
Here are some of the numbers…

• The Niagara River is about 58 kilometres (36 mi.) in length and is the natural outlet from Lake Erie to Lake Ontario.
• The elevation between the two lakes is about 99 metres (326 ft.), half occurring at the Falls themselves.
• The total area drained by the Niagara River is approximately 684,000 square kilometres (264,000 sq. mi.).
• The average fall from Lake Erie to the beginning of the upper Niagara Rapids is only 2.7 metres (9 ft.)
• Below the Chippawa-Grass Island Pool control structure, the river falls 15 metres (50 ft.) to the brink of the Falls.
• The deepest section in the Niagara River is just below the Falls. It is so deep it equals the height of the Falls above, 52 metres (170 ft.).
• The Upper Niagara River extends 35 kilometres (22 mi.) from Lake Erie to the Cascade Rapids, which begin 1 kilometre (0.6 mi.) upstream from the Canadian Horseshoe Falls.
• At Grand Island, the Niagara River divides into the west channel, known as the Canadian or Chippawa Channel, and the east channel, known as the American or Tonawanda Channel.
• The Chippawa Channel is approximately 17.7 kilometres (11 mi.) in length and varies from 610 to 1220 metres (2,000 to 4,000 ft.) in width. Water speed ranges from 0.6 to 0.9 metres per second (2 to 3 ft. per second). This channel carries approximately 60% of the total river flow.
• The Tonawanda channel is 24 kilometres (15 mi.) long and varies from 460 to 610 metres (1,500 to 2,000 ft.) in width above Tonawanda Island. Downstream, the channel varies from 460 to 1220 metres (1,500 to 4,000 ft.) in width. Speed ranges from 0.6 to 0.9 metres per second (2 to 3 feet per second).
• The Niagara Gorge extends from the Falls for 11 kilometres (7 mi.) downstream to the foot of the escarpment at Queenston.