The government is looking at an uninhabited part of Lamma Island in its search for more housing sites, tabling options that would yield up to 2,800 flats.
But residents and environmentalists caution against overdeveloping the island, long a haven for wildlife as well as urbanites escaping the city's bustle.
The land under consideration - according to the consultation document the Planning Department released yesterday - covers 60 hectares in Sok Kwu Wan, including a former quarry, in the middle of the island.
Of the two options put forward in the study, the "Seaside Living" concept would yield between 2,000 and 2,800 flats for a population of up to 7,000.
Private and subsidised housing - but not public rental homes - would be considered under the concept, with flat sizes ranging between 500 and 1,000 sq ft. A 12-storey limit would be set for the buildings, and an existing man-made lake would be partially filled to cater for a higher-density development.
The other option, the "Seaside Paradise" concept, which focuses more on tourism, would produce 1,000 flats and feature resort-style hotels and a marina.
Lamma resident Damon Wong Chun-pong said residents had expressed their reservations about having a densely built environment on the island during a meeting with study consultants this year.
"We are not against development. But we've had only village houses on Lamma and any new housing would better come in more or less the same style and height," Wong said.
"We do not want to see the area dominated by luxury homes strictly managed by one single developer like Discovery Bay. This would run against the village lifestyle and the natural scenic character of Lamma."
Conservancy Association campaign manager Peter Li Siu-man said the scale of the proposed development was too large, warning of the possible ecological effects.
"Remember that there are ecologically sensitive areas for green turtles in south Lamma. Any drastic change in the middle part of Lamma is likely to impact both the north and the south," Li said. A resort and character hotels of a smaller scale, rather than a housing estate, would be more suitable for the area, he added.
The Planning Department will hold three public forums next month to collect views. A development plan is expected to be finalised late next year.