Housing Development Board
Ecological Placemaking, Biodiversity Survey & Impact, Ecosystem Service
2021 - ongoing
Yishun N3C27 Housing
Khatib Bongsu was once an extensive mangrove network permeating through the Yishun district. Over time the area underwent rapid urbanization resulting in ecological connections being severed and habitats becoming fragmented. With the onset of the N3C27 development, the opportunity to restore and strengthen these connections between the existing young secondary forest on site, the adjacent mangrove patch of Khatib Bongsu and waterway link to Yishun Pond, was created.
The site was envisioned to be a residential district adjoined by a neighbourhood park. Surbana Jurong recognized the potential to celebrate the ecology of the site by retaining the young secondary forest in the neighbourhood park which would continue to grow and act as a core habitat space for wildlife. This was accompanied with the integration of a unique wetland space that would create new habitat and serve as an ecological stepping stone for water-dependent fauna transiting between Khatib Bongsu and Yishun Pond. The neighbouring residential precinct would not only enjoy the natural serenity provided by the park but within the establishment itself, thematic ecological zones were created for educational and recreational purposes. The site was designed in a mindful manner to promote human-wildlife coexistence without conflict.
Day and night surveys were conducted to identify the species at the secondary forest patch on site.
Key species found at the secondary forest patch on site.
To develop an ecological strategy to ensure the secondary forest on site can be conserved while ensuring the wider precinct is ecologically designed and that the urban fabric has minimal environmental impact.
bioSEA took an ecological design approach to identify the potential of the secondary forest on site and its ecological connectivity to the Khatib Bongsu mangroves.
We conducted a biodiversity and soil survey of the existing site revealing up to 190 species of animals with the secondary forest patch hosting 178 species and having the highest insect diversity. The soil in the patch also relatively healthy and showed high beneficial microbial activity. These findings allowed us to develop a core conservation zone for the neighbourhood park with boardwalks that skirt around the buffer zone ensuring minimal disturbance to the ground.
Together with Surbana Jurong, we were able to celebrate the ecology of the site by retaining part of the young secondary forest in the neighborhood park which would continue to grow and act as a core habitat space for wildlife. This was accompanied with the integration of a unique wetland space that would create new habitat and serve as an ecological stepping stone for water-dependent fauna transiting between Khatib Bongsu and Yishun Pond. The neighboring residential precinct would not only enjoy the natural serenity provided by the park but within the establishment itself, thematic ecological zones were created for educational and recreational purposes. The site was designed in a mindful manner to promote human wildlife coexistence without conflict.
There is a lack of guidance on how to design with nature especially in residential districts of Singapore due to nature and built landscapes being treated as separate entities with minimal overlap. This warranted the creation of the Ecological enhancements & Design considerations report which not only communicated to landscape architects how best to include nature in their design but also better understand how to establish and maintain these natural zones with minimal human intervention. This included advising on the creation of different habitat types i.e., grasslands, wetlands, secondary forests for use by various fauna who would aid in its sustainable maintenance over time. The environmental impact mitigation strategies outlined how best to curtail negative impacts before, during and after the construction phase. This included constructing in phases and barricading crucial core habitat zones in the young secondary forest before construction began.
With all the above assessments and recommendations put forward, bioSEA piloted a new framework that factored in landscape ecology principles pertaining to habitat type, patch size, extent, quality and ecological connectivity metrics, to quantify the overall ecological value of the site pre- and post-construction. The assessment showed how valuable the inclusion of the wetland was, not only in terms of connecting the current landscape but in terms of creating the foundation for future development which could potentially see the naturalization of the adjacent drain and the formation of a wholly connected water system from Khatib Bongsu to Yishun Pond.
Lastly, the ecosystem service evaluation is currently underway to assess the projected benefits residents and visitors can derive from the proposed design of the development.
Overall, our surveys revealed a high ecological value of the site that were followed up with design approaches and assessments that allowed us to conserve, protect and celebrate the landscape as best possible. This allowed the project to be dubbed as ‘Back to Nature’.
The design received the International Federation of Landscape Architects (IFLA) Award of Excellence 2022 for their strategic greening and masterful execution of biophilic and ecological design.
Cover Image: A freshwater wetland designed at Yishun N3C27 housing to complement the salt mangroves adjacent to the site.