2012-12-31 15:32:02

Urban River Integration for the 21st Century: A new vision for blue-green city infrastructure which addresses the multi-facetted needs of water supply and flood protection while creating spaces for people and nature in the city

Background Information


Singapore doesn’t have enough drinking water. It has no natural aquifers and 60 percent of its water supply is currently piped from Malaysia into the city.

To further complicate matters, expansive development and a significant population increase since the 1960s means that the city has also faced drought, flooding, and water pollution. Drains and canals, including the Kallang River which ran in a concrete channel along Bishan Park, were built to alleviate widespread flooding. One problem was solved but now, 30 years later, a concrete channel is no longer an acceptable element of the urban infrastructure system. There are better and more integrated solutions. In addition, these channels are dangerous and every year result in loss of life due to accidents.


Another topic of concern was the dramatic increase of people living close to the park. The density of the neighboring housing areas has increased constantly for 30 years. Bishan Park is the only big park in the surrounding area and highly used, which resulted in yearly visitors of more than 2.5 million. The park was built in the late 1960s with amenities that reflected the needs and style of that time. It needed both a face lift and an upgrade as the needs have changed considerably over the last decades.


The former park was more or less a monoculture: wide lawn areas with randomly located trees, with very little biodiversity. Modern parks have to represent the local flora and fauna and integrate solutions to support specific habitats.

Goals of the Initiative

The goal was to transform the Kallang River and Bishan Park into a new and unprecedented vision for blue-green city infrastructure which addresses the multiple needs of water supply and flood protection while creating spaces for people and nature in the city.


The above goal required a totally new design process as all city agencies, designers, and stakeholders needed to be involved from the beginning in the planning process.


NParks and PUB had to define their new roles within this system, as park and water infrastructure were integrated into one element. New responsibilities for design, permitting, and maintenance within the agencies had to be developed.


For example, the bioengineering river bank stabilization system, which had been used around the world, had never been used in a tropical environment and would need to be tested. One hundred percent of the concrete from the former channels was recycled and reused in the park. Water used in the park is cleansed with a natural cleansing system (cleansing biotope) which saves 150,000 liters of drinking water per day. About 30 percent of the trees in areas of heavy reorganization could be saved through relocation within the park.


School kids designed park elements and never before had new interactive medias platforms like Facebook and Twitter been used for public commenting on a design project in Singapore.


Before the park was reconstructed, a biodiversity monitoring report took place. Yet, in the new park, this biodiversity monitoring has continued to measure and understand the changes. The highly innovative bioengineering systems (seven special techniques) are monitored on a monthly basis to learn and understand the development.


It was a major goal to reconnect the citizens with lost nature: a place to take one’s shoes off and get closer to water and nature. The park should become a cultural focal point. Lost cultural heritage and practices like community gardening shall be reintegrated (reviving the “Kampong” spirit) and space for new urban cultural activities like nature watching shall be created.

Parties and Partners to the Initiative and Resources Used for Implementation

Public (Client):

PUB, Singapore’s national water agency (

NParks, Singapore National Parks Board ( )

Public Participation: Survey of users of the old Bishan Park, active design workshop with adjacent schools, collecting comments from the Grass Root Initiative of Singapore

Project Team:

Concept/Design: Atelier Dreiseitl (;

Project Engineers: CH2MHILL ( )


Peter Geitz, Bioengineering

The resources used for implementing the initiative include:

The project was funded partly by PUB and partly by NParks (the first time ever in Singapore that two agencies split responsibility).

Innovation for the Initiative

The Kallang River/Bishan Park initiative can definitely be described as revolutionary for Southeast Asia. It is the first project of its kind, where water infrastructure is aesthetically and technically integrated as well as the reconnection of the citizens to a vanished natural area has been so consequent and successful. In the 1970s, all rivers had been transformed into concrete channels; now it is the starting point of an island-wide re-integration of natural water cycles, biodiversity, and human interaction.

The so-called ABC Program (Active, Beautiful, Clean) regarding the water policy of Singapore is a strategy to save the drinking water resources, decentralize the storm water management system, and reconnect the people to urban water areas. We developed a Master Plan Concept for the Central Watershed that integrates water– — Singapore’s life blood — into the city in new and previously unimagined ways. Landscape and urban planning visualizations have been combined with an engineering approach, bringing a fresh and integrated look at what is possible. The primary challenge is to manage water in a way that restores Singapore’s waterways and creates waterscapes that enrich the city, bringing nature and humanity in harmony.

The result will be an integrated vitality network evident throughout the central watershed of blue (water), green (adjacent habitat and open space), and people – one that is active, beautiful, and clean.

This concept has resulted in a policy which was adopted by the government of Singapore and is now mandatory for all future developments.

Another important innovation aspect is the bioengineered technology. Bioengineering was used to build a system that stabilizes the banks and slopes with living plant material. Stabilization is reached through the root connecting with the soil and coverage of the ground/soil to avoid erosion. This technology, which was developed in Europe and the USA, had never before been used in a tropical climate (as far as we know). We had to find plants with special growth aspects (root system, vitality, pioneering qualities, etc.) that are suited for a tropical climate. The special construction technology with the adapted plant selection was tested in a research slope before the big project started. After we got positive results we integrated this technology into the overall park.

Only parts or specific aspects have been used from other project experiences. The combination is unique and unprecedented.

Obstacles and Solutions for Innovation

Resistance was present in the beginning against the bioengineering system, as this system had never been used before in a tropical climate. The test area that was built helped to show that this technology is reliable and would work.

Outcomes and Assessments

Outcomes achieved are as follows:

The people love the new park. They started to immediately touch, walk through, and observe the natural habitat as they re-enter the new park. Small children, students, and adults take study tours to the park. People meet to do bird-watching and shoot videos of rare animals in the park, which has widely spread on the internet. This intensive connection created an attitude of care for the park. Organizations have been established to protect and develop the park further.

The city’s maintenance team had to learn a totally new maintenance procedure. Natural systems need different care than a concrete channel. This learning experience will ease the establishment and integration of future projects similar to Bishan Park.

The construction of Recycle Hill, which was made of the demolished concrete from the channel, showed how resources could be saved and “garbage” integrated into a natural design.

The connection to the river, which is in essence one of the sources of people’s drinking water, creates a totally new connection and understanding of the water that comes out of people’s tap. Also the cycle of the rising and decreasing water levels due to rain tells people the story of integrated rain water management.

People from governments of many countries in Asia have visited the park. The feedback is overwhelmingly positive and the people go back with the vision to do something similar in their home country – every city in Asia has similar projects and problems.

Assessments are as follows:

A 30 percent increase of the biodiversity has been measured. The measuring is permanently done by NParks (National Parks Department), including regular counting of animals and development of rare plant species.

Water quality is ensured through a cleansing biotope and the river is monitored by PUB. 

Methods Applied

Bioengineering: Monitoring of plant development, root strength, etc. (this data is unique and the first of its kind in Asia)

Plant habitats: Training for NParks staff in the special maintenance of plant habitats.

A warning system was installed to warn people that are adjacent to the river if the water starts to rise due to rainfall.

Benefits to Other Cities

The most important aspect is certainly the integrated storm water management with the creation of a natural river. This creates a totally new possibility for cities to deal with their rivers, manage storm water, bring back nature into the cities, and create parks for recreation and healthy citizens.

Cities have always been seen as the opposite of nature whereas nowadays we have to find a way to integrate nature and cities. Cities have to become more resilient; climate change comes with higher risk of flood events and drought periods, which will effect cities extremely and in the relatively near future. This concept that works with decentralized integration is perfect for adaption to future challenges. It holds back storm water, it cleanses the drinking water resource, it allows rare flora and fauna to come back into the city, and it gives space, contemplation, and nature experiences to people. This holistic concept is one piece of a concept that can help assure a future for our planet.