A recently retired Vancouver Inspector who helped plan the initial stages of the Stanley Cup security plan says he would have begged the city to reconsider its plan to invite huge crowds downtown to view the game on the streets.

Insp. Rick McKenna says placing the live sites within blocks of each other created a dangerous concentration of unruly fans that didn't give police enough options to fight any disturbance that could have erupted.

"When you get numbers that high, there's little you can do when the crowd turns," McKenna told CTV News.

And turn it did – police estimate that the 150,000-strong crowd gave rise to about 30,000 people reveling in mayhem, fighting, torching cars, and vandalizing businesses.

Today Vancouver Mayor Gregor Robertson admitted that there were too many people watching the game on Granville Street, so the city had to expand to Georgia Street. But he admitted even that wasn't enough space.

"The size overwhelmed the site and there were so many people downtown beyond who was in the fan zones," he said. "There were 150,000 people and the capacity was 25,000 to put that in perspective.

"What took place was far beyond anything anyone had anticipated," he said.

But he said Vancouver Police Chief Jim Chu had discussed the plan and all parties signed off on it.

"This was a discussion through city management, the corporate management team, to look at increasing the site of the live site," he said.

The eventual operational plan was a far cry from McKenna's plan that he presented at the March 16, 2011 meeting of the police board, about two weeks before he retired.

In the March plan, he recommended about 350 officers to deal with a Game 7 where fans were not invited downtown. He was using estimates that showed many fans were opting to celebrate in their local cities at celebration sites such as Surrey and Abbotsford.

"We'd seen significant reductions in crowds coming to the celebrations," said McKenna. "We'd seen people stay in sites around the Lower Mainland."

When the city decided to put in outside venues to watch the game, they were popular and a shoulder-to-shoulder crowd on Granville Street for round three needed accommodation in larger and larger venues.

The city closed Georgia Street for a fan zone for the first time, and fans flocked there. The trouble was, according to McKenna, that was too close to where fans were already gathering, in the bars on Granville Street and in front of the CBC building.

"When you get that size of a crowd there aren't enough officers in the Lower Mainland to control it," McKenna said.

"One of the aspects of crowd management you push a crowd to dissipate it. Where are you going to push them? Down Georgia street to the Bay? Up Granville Street? Where are they going to go? You need an area to push them to and the downtown core doesn't give you an area to push the crowd to dissipate them. You're just pushing them into another potential target area."

A confidential operational plan for round 4 of the Stanley Cup Final made public yesterday gives some detail to how the Police's vision of security changed from March.

They asked for, and got, 100 extra RCMP officers to deploy around the city. They also upgraded the threat of public order disturbance to medium, which is about the same as a rowdy concert or a protest.

That implies police did not expect a riot, though they did prepare for that eventuality.

City Councilor Suzanne Anton, who is running for mayor in the next civic election, said the event was run out of the mayor's office.

"He never brought it to council," she told CTV News. "Gregor Robertson needs to take full responsibility."

Robertson said he was awaiting a provincial review in the riot, due out by August, which would explain clearly what happened. He added that he was confident future events would be handled well by police and city staff and would remain safe.

Councillor Geoff Meggs said that second-guessing the police or city staff isn't productive.

"I think that Chief Chu is being put in the position of [Canucks Coach] Alain Vignault. Not all of us can coach a Stanley Cup contender, but we wish we could and believe we can, and everyone is offering plenty of over the shoulder advice," he said.

McKenna says he believed that under the circumstances the VPD behaved exceptionally well.

But he would have liked to see more private security in the fan zones, so that no alcohol or weapons could be brought in, as well as changing fencing so angry fans couldn't pick up the fences and use them against the police.

"In my opinion the perfect scenario is, spread out the crowds, have the screens in all parts of the city, and give people other places to go," he said.