Concerned residents were left frustrated after being told they should lodge their complaints over a possible new incinerator on a post-it note.

The new style public consultation, which focused on waste management policies for the future, was held at Croydon Clocktower on Monday night.

Several residents and campaign groups came armed with tough questions to pose to the authority over the possibility of an incinerator included in the waste plans for Croydon.

But to their surprise there was no presentation or question and answer session. Instead visitors were encouraged to leave post-it notes with their questions or queries on the display boards around the room.

Alternatively, they could hold informal one-on-one discussions with officers in charge of the consultation, which is looking at possible sites across Kingston, Croydon, Sutton and Merton – members of the South London Waste Partnership – for any future waste management facilities.

Andrew Pelling, MP for Croydon Central, said the consultation would have made Alastair Campbell proud.

He said: “I think it was done in such a way to ensure there was no coming together of views at the meeting, there was no lightning rod. This was less of a consultation and more of a PR exercise.”

Shasha Khan, of the Croydon Green Party, said: “We would have preferred to see a proper question and answer session with a presentation detailing everything.

“With this format you limit the risk of people asking some difficult questions in public in front of everyone, putting the project manager into a corner.”

John Cheetham, vice chairman of Waddon and Broad Green neighbourhood partnership, said: “It is not what I expected. If I ask a sensible question I want other people to go ‘yes’ and gauge their reaction, and then hear the answer. The format makes it difficult to open the debate.”

But the council is adamant the consultation was a success, and cites an exit survey which found many positive remarks on the new format.

A council spokesman said: “Of those who commented on the event as they left, more than twice as many were happy with the format as those who said that they had expected a different approach. There are no plans to substantially change the format of future events.”