Transforming the city both green and blue is how Singapore can achieve a highdensity
and liveable environment, said Centre for Liveable Cities Executive Director
Khoo Teng Chye to policy makers, planners, developers, architects and landscape
architects gathered for the recent “Dense and Green Building Typologies: Architecture
as Urban Ecosystem Symposium”. They were brought together by Future Cities
Laboratory (a programme of the Singapore-ETH Centre) and hosted by the Urban
Redevelopment Authority to discuss how dense and green building typologies can
contribute to developing compact, yet, highly liveable future cities.
When we plot the liveability of cities on a chart, positioning “Liveability” against “Population Density”,
most of the indexes rank cities like Vancouver City, Sydney and Melbourne, among the most liveable
cities. These tend to be huge cities with low density. However, there are a few high-density cities that
liveable—Singapore is one of them.
As this symposium, I will focus on how Singapore has improved our liveability despite becoming
denser through our urban systems approach of making the city green and blue. I will discuss how we
made Singapore, first into a Garden City, then a City in a Garden, a City of Gardens and Water, and
beyond this, a City in Nature.
When we think about high density, we tend to imagine concrete jungles. In the case of Singapore,
our approach to greenery is not about planting lots of trees, but how greening is in tandem with
urban planning and development. We describe this as the system approach of adopting a holistic
and comprehensive vision, which translates into actionable plans and policies.
The greenery urban systems approach has three main thrusts. First, we have a hierarchy of
greenery within the urban matrix. Instead of creating parks anywhere and everywhere, we built
national parks such as the Botanic Gardens and Gardens by the Bay. Regionally, we have parks such
as the West Coast Park, East Coast Park and Bishan-Ang Mo Kio Park. Further down, we have town
parks, and within each town we created neighbourhood parks and community parks.
Second, we wanted to make greenery prolific and to transform Singapore into a canopy of green.
We looked into the type of trees for planting and implemented standards to make sure greenery
is pervasive within the urban fabric of Singapore. This was achieved by overlaying greenery on
the city’s various networks, such as the roads in the form of road side trees and covering concrete
structures like retaining walls, parking lots, and drainage reserve (now Park Connectors) with
Third, we implemented rules, incentives and land zoning policies that require for green buffers to
be created, and for rooftop and skyrise greenery to be incorporated within the buildings. As a
result, you can see from the satellite image by NParks that our green cover grew from 35.7% in
1986 to almost 50% in 2010 even as we continue to urbanise. Over time, this has become our
Turning the City Blue
Now, I want to talk about water and the Active, Beautiful, Clean Waters Programme (ABC Waters).
Water is an existential issue in Singapore. While we receive an abundant rainfall of 2400mm a year,
we do not have enough ground water. We have since diversified our water sources; investing in
technology to create alternative supplies in the form of NEWater and desalinated water. One of
the most important tasks for PUB, the National Water Agency, is to systemically harvest as much
rainwater as possible, and close the water loop to produce NEWater. Originally, we had three
reservoirs, but now we have created 17 reservoirs and turned almost two-third of the island into a
The idea of ABC Waters is to get people to treasure water as a resource by bringing them closer to
water. Beyond that, water can also be managed as an environmental and urban asset that enhances
the city. The Blue Map shows that Singapore has 8,000km of rivers, drains and canals. Many of them
are ugly water pipes and hard-looking concrete monsoon drains which can be transformed into
vibrant and beautifully naturalised streams, rivers and lakes.
The genesis of ABC Waters began with the Urban Redevelopment Authority (URA) when the agency
started the Waterbodies Design Panel in the late eighties to pilot some of these ideas. You will notice
that Sungei Api-Api looks like a river of mangroves, however, it is actually a monsoon drain with planted mangroves to soften the banks of the river.
The Bukit Panjang Stormwater Pond is also one of
the first projects that was naturally landscaped.
Unfortunately, these projects were phased out
due to the lack of a systemic approach to sustain
and institutionalise the programme.
When I joined PUB in 2003, we began
implementing ABC Waters by developing
Singapore into three catchments and drew up a
masterplan to identify opportunities to naturalise
the waterbodies. We identified about 100 projects and systemically sought budget approvals to build
the sites over a 5-year period. One of the most important justifications we used for these sites is how
the programme enhances property value. This is especially true in the case of Bishan-Ang Mo Kio
Park. After the park was announced, property prices of the surroundings went up immediately.
Another example of our blueing process was the planning and construction of Punggol Waterway by
PUB and the Housing and Development Board (HDB). We cleaned up Lorong Halus, an old solid waste
landfill, and dammed the Punggol and Serangoon reservoirs. Instead of building an underground
pipe to connect the two reservoirs, we created an open waterway, and in the process, many new
waterfront neighbourhoods. These are the many opportunities that water presents. In the west, JTC
created an eco-industrial park at the fringe of Nanyang Technological University. Instead of building
a conventional drainage system, we created the Jurong Eco-Garden, which is now a constructed
freshwater wetland that seamlessly intersperses with building parcels. There are also other examples
such as the vegetated bioswales and bioretention basin in Windsor Park Estate and Waterway Ridges.
Mainstreaming ABC Waters
We need to move beyond just beautifying water bodies, but to see water as a much broader
opportunity to enhance the urban environment. This means mainstreaming ABC Waters, and looking
at how to integrate water upstream in the urban planning process. This is being pursued by URA, PUB
and other agencies following a workshop organised by CLC in 2015. Beyond looking at waterbodies,
we should look at water as it falls on the land and buildings, and plan for how we can make water
pervasive in the same way we are doing for greenery.
Bishan-Ang Mo Kio Park is an example of this. Instead of just beautifying the canal, agencies worked
together to naturalise and integrate the canal into the park. The concrete rubbles of the monsoon
canals were recycled. In this process, we also resolved the capacity of drainage through bioengineering
techniques and created a bigger park.
Singapore, more than any other city, has the opportunity to make our city as blue as it is green. We can
learn lessons from greening, and apply them to mainstream ABC Waters. We have documented the
lessons, ideas and projects of the ABC Waters in our Urban Systems Studies publications, which are all
available on our website.
Towards a City in Nature
Combining the green and blue in our city has brought about an increase in biodiversity where trees
and flowers attract animals such as otters, hornbills and many more. The National Parks Board
(NParks) has a truly ambitious vision where they see Singapore as a natural ecosystem. The four
zones of high “Biodiversity Core Areas” are left relatively untouched, namely the Central Core which
consists of the Central Catchment and Bukit Timah Nature Reserve, the Western Core includes the
Sungei Buloh Wetland Reserve, the Northern Core is made up of Pulau Ubin and Coney Island, and
the Southern Core includes the entire stretch of the Southern Ridges. At each of these areas, NParks
created “Nature Ways”, which are green buffers that improve the ecological connectivity of these
areas. At the microscale, there are tremendous opportunities for architects and engineers to turn
every single project to be part of this urban ecosystem.
Beyond parks and waterbodies, our Concept Plan review should also have a City in Nature plan. Our
current Water-Sensitive Urban Design (which is an Australian expression that we call ABC Waters
design features here) should shift towards Nature-Sensitive Urban Design. This is an evolving
approach that we should try to encourage. We should push for such urban designs to be incorporated
in the land sales considerations. We can also look into developing buildings and infrastructure based
on the principles of building with nature.
This is an exciting area where there are tremendous opportunities and challenges for research. There
will be questions of why we need a City in Nature, whether it is for health, resilience or aesthetic
reasons, hence we need a better understanding in many of these areas. There are also many new
developments that offer opportunities to undertake pilot projects, such as HDB’s upcoming Tengah
“Forest Town”, Singapore’s second Central Business District (CBD) in Jurong Lake District, and
reclaimed land on Pulau Tekong.
I am optimistic that we can become the first City in Nature. More than any other city, Singapore
has the propensity to make this happen. This should not be just a wish but we have to make sure it
About the Speaker
Mr Khoo Teng Chye
Mr Khoo Teng Chye is currently the Executive Director for the Centre for
Liveable Cities, Ministry of National Development (MND), Singapore.
He was formerly the Chief Executive of PUB, Singapore’s National Water
Agency (2003 to 2011), Chief Executive Officer/Chief Planner at the Urban
Redevelopment Authority (URA) (1992 to 1996), Chief Executive Officer/
Group President of PSA Corporation (1996 to 2002), President and Chief
Executive Officer of Mapletree Investments and Managing Director (Special
Projects) of Temasek Holdings (2002 to 2003).