Thirteen people died during the epidemic, and more than 180 individuals contracted the disease.
The final report released by the regional director of Quebec City's public health department last December reveals the outbreak was confirmed on July 26.
The report shows that internally, the department prepared to go public with the news, notably by creating a webpage.
But the city's public health department didn't issue the first public notice until five days later.
Now another document obtained by Radio-Canada through an access to information request shows the city’s health officials also took four days to plan a news conference about the outbreak in August.
The conference revealed a spike in the number of cases and discussed the measures being taken to combat the epidemic.
But the regional director Quebec City’s public health department said it was important for officials to plan how they were going to deal with the outbreak.
"We would do the same thing now with the information that we had at the time," said Dr. François Desbiens.
He said they decided it was best to wait to release all of the information at once.
Quebec City resident Solange Allen said her husband, Claude Desjardins, might still be alive if they had been better informed.Desjardins was among the first victims of legionnaires' disease.
Allen says if the city had warned residents about the symptoms, her husband would have seen a doctor earlier.
The province is working now on putting together a guide in the case of an event of another outbreak.
Desbiens says a communications strategy will be part of that guide.A public coroner's inquiry into the deaths caused by the Quebec legionnaires' outbreak is currently underway. Hearings will begin at the end of April.