As others have said, certainly not an Osprey based on your observations. From what you describe, it sounds like a Swainson or possibly a Red Tail Hawk which are very common in the city. If you drive the perimeter of Nose Hill Park at this time of year you'll likely see a dozen of either species perched on light standards awaiting their next meal below at most times of the day. They are also common perched on light standards along Stoney Trail.
The Following User Says Thank You to FLAME ENVY For This Useful Post: