Innovative engineering solutions for flood and water supply are helping make Singapore fit for the future
The Kallang River Restoration is a sustainable engineering project which addresses water supply and flood protection while creating spaces for people and nature in the city. Bioengineering was used to ecologically restore the river, significantly increasing flood capacity and improving water quality.
Singapore has no natural water aquifers; the Kallang River is major drinking water supply component. Whereas before the concrete channel had a maximum width of 24 m at flood capacity, the river can now spread to 100 m thanks to the re-profiled bioengineered cross-sections. Natural looking meadows are in fact innovative, reinforced vegetation technology. Local residents have a larger park with access to the river, Singapore's National Water Agency has more water in better quality.
The use of bioengineering to stabilize the river banks is a first for Singapore and a new reference for soil stabilisation in the tropics. A 60 m test reach was constructed at one of the side drains into the park. 10 different soil bioengineering technologies were systematically tested. Seven were then selected for use along the main river. These include fascines, rip-rap with cuttings, geotextile wrapped soil-lifts, brush mattresses with fascines, reed rolls, planted gabions and geotextile with plantings.
Hydraulic modelling allowed the riverbanks to be reinforced only at the points where this is needed, reducing construction costs. The creation of diverse flow patterns characteristic of natural river systems makes the new river ecologically resilient; the park's biodiversity increased by 30%. The cost efficiency, simple technology and eco-social benefits of this project make it a pilot reference for sustainable water engineering for developing and developed countries alike.
JV Project Designer: Atelier Dreiseitl (www.dreiseitl.com)
JV Project Engineers: CH2MHILL (www.ch2m.com )
Bioengineering Consultant: Peter Geitz and Partner JV Project Owners: PUB, Singapore's national water agency (www.pub.gov.sg) and the National Parks Board (www.nparks.gov.sg )