We love dogs too but they aren't permitted at San Diego Bayfair.
Only service animals with appropriate documentation are allowed within the event site on East Vacation Island, Crown Point and Fiesta Island, per the City of San Diego.
Fiesta Island Dog Park
The general public can access the dog park on Fiesta Island during San Diego Bayfair. No standing or viewing is allowed from the berm on the westside of the dog walk area.