The number of collisions on GTA highways with HOV lanes sky-rocketed during the Pan Am and Parapan Am Games.

Police say collisions jumped by 73 per cent to 1,720 during the time the HOV lanes were in effect this year, compared with an average of 993 collisions during the same time period in the previous four years.

The lanes were in effect from June 29 — 11 days before the Pan Am Games opened — through July 26, the end of the Parapan Am Games.

OPP Sgt. Kerry Schmidt says police don't keep statistics on which lanes collisions occur.

Schmidt says the numbers reflect collisions that occurred on the stretch of road where HOV lanes existed during the games, but may not have occurred in the lanes themselves.

As for why the number of accidents was up during the games, Schmidt says, "If there's a change in roadway design, it can take a while for drivers to get used to it."

The HOV lanes were installed on the 400-series highways, the Queen Elizabeth Way, the Gardiner Expressway and the Don Valley Parkway to speed up traffic, and get Pan Am officials and athletes to events faster.

Officers from the Ontario Provincial Police and the Toronto police issued tickets for any vehicles in the HOV lanes with fewer than three passengers.