The eco-camp has been proposed by Tung Wah Group of Hospitals, one of the largest and oldest charities in Hong Kong. Its community services director, Stephen Ng Chi-wing, stressed the plan did not involve filling in any wetland.

'To promote ecological education among young people is one of the project's missions,' he said. 'We will take all measures to preserve the environment as far as possible during the construction period and when the camp operates.

'The heritage and ecological environment in Tai O are valuable resources for education of young people. We believe our camp will make good use of these natural resources and benefit both the campers and the Tai O community,' he said.

The Lands Department said it had received a preliminary proposal in November last year from the group for a site to build a holiday youth camp. A spokesman said the proposal was being studied by various government departments.

A spokesman for the Tai O Rural Committee said the plan would be discussed at its next meeting on April 17. He denied the site was part of the wetland and said it comprised 'only reed fields'.

All parties concerned declined to reveal more details about the camp, including its cost and construction timetable. However, under a Planning Department study in 2001 on how to revitalise Tai O, the site was zoned 'recreation' and reserved for holiday accommodation.

Tai O, the fishing village at the western tip of Lantau, is known as the 'Venice of Hong Kong'. The village is located mostly on the banks of the river and surrounded by hectares of wetland, which is home to wading birds such as the little egret and grey heron.

Ho Pui-han, executive officer of the Association for the Environment and Development of Tai O, said the site was of great ecological value.

'Filling up this site, which is indeed a wetland, would have a serious effect on the ecology of nearby wetlands, the neighbouring reed fields and mangrove fields,' she said. 'This is a classic irony. How can one damage a natural wetland and then claim to promote eco-education and conservation?'

Wong Wai-king, a residents' representative in Tai O, said she was shocked by the plan.

'The authorities always try to waste taxpayers' money on construction projects that will destroy the natural scenery here. Why can't they just leave it alone?' she asked.

Ng Cho-nam, a director of the Conservancy Association, described the plan as 'ridiculous'.

The ecology of Tai O has already been affected by construction. Two million cubic metres of mud was dredged from an abandoned salt pan area in Tai O in 2003 to build a typhoon shelter. But the four-hectare anchorage, which cost HK$260 million, has been mostly empty since the project was completed in 2005.