Even the dugongs will do their bit to draw more visitors to Darling Harbour during its $2.5 billion redevelopment.

But a proposal for a temporary fruit and vegetable garden down the centre of Pyrmont Bridge – fertilised by organic waste such as the Sydney Aquarium’s dugong food scraps – has drawn the immediate ire of pedestrians and cyclists, who are worried the project could worsen congestion problems on the bridge.

Fears garden project will increase congestion: Proposed temporary fruit and vegetable garden on Pyrmont Bridge.

Dubbed Amaze, the ‘‘world-first experiment in environmentally sustainable design’’ will be made up of three tunnel-like sections of trellis garden, each 60 metres long and almost six metres wide.

If the plans are approved by the City of Sydney, the partnership between the Sydney Harbour Foreshore Authority and sustainability entrepreneur Joost Bakker will be installed from October.