SINGAPORE - A rustic landscape with meandering hills, a boardwalk across a marshland and a unique rain tree "island" set in the middle of a lake.

This will be the sight that will greet residents of the upcoming Bidadari estate, which will have 10,000 Housing Board (HDB) units and be progressively completed by 2022.

Details of Bidadari Park were revealed on Sunday (May 5) at an interview with the HDB team which led the development of the project.

The park is a multi-agency collaboration involving the HDB, National Parks Board (NParks), PUB, Singapore's national water agency, and National Heritage Board (NHB).

At 10ha, which is the size of about 15 football fields, the park is among the largest done by the statutory board.

The park will take up 10 per cent of the estate's space and nestle snugly among the residential blocks, with trails connecting seamlessly through the estate.

The HDB team sought to retain as much of Bidadari's natural woodland as possible, and did so via a three-year-long analysis, said Mr Leonard Cai, deputy director (landscape design office) at the HDB's building and research institute.

"We went down to the site to map out the position of trees, (to see) where are the areas with the least amount of vegetation so that we could place new trails there, so as to cause the least disturbance to existing biodiversity," he said.

He added that the team also engaged nature groups to identify and retain "bird studios" where birds are frequently sighted.

In fact, Hillock Park, a smaller adjacent 1ha park that is an extension of Bidadari Park, will be a bird sanctuary of sorts for species such as hornbills and owls, and residents will be able to access vantage points at the rooftop garden of the nearby Woodleigh Glen residential project.

This is encouraging news for bird watchers such as Ms Heng Juit Lian, an executive landscape architect at the HDB's development and procurement group, who is also part of the Bidadari Park team.

"It is a step forward having more of such places to view and appreciate birds and continue the hobby. We do value this kind of spaces," she said.

Efforts were also made to retain more than 350 trees, including a century-old tembusu tree.

Park features such as the lake, trails and viewing sheds have been designed around the trees.

For example, a playground will be centred on an existing banyan tree, and a rain tree on a little island will be the focal point of the new Alkaff Lake.

In total, the park will have more than 2,000 trees, including more than 150 species - some critically endangered ones - transplanted from other areas.

A unique eco-link bridge shared by both park users and wildlife will also be constructed across a road to link Bidadari Park and Hillock Park, which came about from suggestions by the Nature Society (Singapore).

Up to two-thirds of the bridge's 19m width will be dedicated to greenery for small animals to traverse across the parks.

Future Bidadari resident Ng Yiqiang, 30, a social worker, is looking forward to the lush natural features.

"It will be wonderful to have such a green sanctuary right at my doorstep amid the urban bustle."