Several people reported on Twitter that water had reached several rows up into the Saddledome, but the city's emergency management director Bruce Burrell was unable to confirm those reports.
The Calgary Stampede activated its Emergency Management System late Thursday and advised only key staff to come to Stampede Park on Friday.
The Stampede's email system was down, but a page was set up to provide updates.
Organizers said Thursday through social media that all animals had been transferred from the grounds by that point in time. The Stampede is due to start in two weeks, running from July 5 to July 14.
Meanwhile, first-round play at the PGA Tour Canada's ATB Financial Classic was postponed again Friday.
Only a few dozen players made it out for the start of the opening round a day earlier at the Talons Course at Country Hills Golf Club in northwest Calgary. Play was stopped after just 82 minutes because of wet weather.
PGA Tour Canada president Jeff Monday said that following consultation with various organizations, the decision was made to postpone further play Friday.
"With the surrounding communities affected by flooding and the golf course saturated from the excessive rain, we have determined it would be in the best interest of players, volunteers, staff and most importantly the surrounding community to cancel play today," Monday said in a statement. "Through discussions with the sponsors, tournament organization and golf course staff, we plan to proceed tomorrow with the tournament, which would become a 36-hole competition and would carry over scores recorded so far."
The plan is for a 36-tournament to conclude on Sunday night.
Rain was forecast to continue for the next several hours, with Prime Minister Stephen Harper scheduled to tour affected areas with Alberta Premier Alison Redford later Friday.