Canadian divers who said they were with Scuba 2000 in Toronto got in trouble on Sunday while drift diving in the upper Niagara River. One diver at 40 feet hyperventilated and made a quick ascent to the surface because he was having difficulty breathing.
It was a very close call. The divers could have been easily hit by a boat in the river which at this time of year has high traffic. A dive flag is a necessary piece of safety gear especialy in the Niagara River on a hot day in July.
The article:
http://www.buffalonews.com/editorial/20060724/1003700.asp