Formula 1 CEO Stefano Domenicali addressed complaints raised by the teams over flooded hospitality units and leaking roofs during the rain-hit race.
Team personnel, guests and media were also dismayed at the lack of suitable parking provisions, with only a muddy track linking an overflow car park to the paddock.
Domenicali apologised to team principals at a meeting at the track on Saturday morning for the working conditions, which are at odds with their ambitions for the race.
A statement from the organisers sent to Motorsport.com said: "Regarding [the car park] and egress, we sincerely apologised and understand the frustration that this has caused, we acknowledge that what transpired is unacceptable and put in mitigation measures for the Sunday including an alternative route.
"We are well aware that leaky tents and media booths are not up to the standard we wish to uphold and will be having serious follow-ups with the third parties involved."
The promoter also responded after a breakdown in communication left some race fans unable to enter the track on Friday. A number of spectators were wrongly told that both practice sessions had been cancelled due to the heavy rain.
The promoter blamed the local transport authority Société de transport de Montréal [STM] for the incorrect information.
A statement added: "Regarding the Friday pre-FP1 storm, there was never any communication from the promoter that the sessions were cancelled.
"We communicated to fans in grandstands to evacuate the grandstands due to weather but asked those in suites or permanent buildings to stay put.
"We temporarily stopped fans from entering the circuit for security reasons as they were safer in the subway, their cars, or the casino.
"We understood later in the day that the public transit authority, the STM took it upon themselves to announce a cancellation without our knowledge or consent.
"As soon as the weather front had passed, and it was safe to do so we allowed fans back into the grandstands and back on-site."
The Canadian Grand Prix has a deal to remain on the calendar until 2031 and, this year, enjoyed a record attendance of 350,000 spectators over the three days.
