Police are citing excessive speed and erratic driving in the death of a 21-year-old man from Victoria in a horrific head-on collision on the Sea to Sky Highway just south of Britannia Beach early on Sunday morning (Aug. 8).Squamish RCMP said the man, whose name has not yet been released, was northbound on Hwy. 99 on the S-curve downhill heading into Britannia when he lost control of his Subaru and crossed into the southbound lanes, where he struck a Volkswagen Golf driven by a 50-year-old Squamish resident.The driver of the Subaru died from his injuries and was taken to Squamish General Hospital. The Squamish resident was airlifted to Vancouver General Hospital with serious injuries.Caroline L'Heureux was following the Golf southbound and witnessed the accident. The Whistler resident works at the Whistler Mountain Bike Park and was taking four youths to Vancouver International Airport after a summer camp. L'Heureux said she came around the curve just in time to see the collision, though not how the Subaru ended up in the northbound lane. She managed to avoid being hit by pulling into the northbound land and saw the Subaru fly into the air and hit the road."As I went by I saw the guy's head drop."L'Heureux attempted to help the driver of the Golf and called police.Police have not released the name of the local man but RCMP Cpl. Dave Ritchie said the man is a firefighter who works in Richmond. As of Tuesday (Aug. 10) Ritchie said the man is conscious and his injuries are not life-threatening.The accident closed the highway completely for about 90 minutes before re-opening to single-lane alternating traffic.The accident is the fourth fatal crash this year on Hwy. 99, with a total of 10 lives lost. Seven of those were in a two-vehicle crash near Depot Road on Jan. 31.Ritchie said excessive speed and erratic driving behaviour is believed to have contributed to the accident, which remains under investigation.