Stamford Canal upgrades planned through to 2017

A detection tank and diversion canal will be constructed to increase Stamford Canal's flood protection capabilities.

Both upgrades will be located at the upstream section of the Stamford Canal catchment and will divert stormwater from one-third of the catchment towards the Singapore River, said nation water agency PUB, who is handling the project, in a release.

PUB estimates the detailed design for the construction tenders of these two measures will be carried out during the second half of 2012. Works for the diversion canal are expected to complete by end 2017 and the detention tank to complete by end 2015.

PUB said the new diversion canal, which runs beneath the road surface, will start from Grange Road, along Hoot Kiam Road, River Valley Road and off Kim Seng Road to Singapore River. It will measure about 2 km in length, with width ranging from about 6 metres to 14 metres and depth from 3 metres to 4 metres. 

It added that the detention tank will be built directly beneath a proposed nursery and coach park at Tyersall Avenue. With a capacity of about 38,000 cubic metres, the detention tank will temporarily store excess stormwater from the drains in Holland Road. After the rain subsides, the water will be pumped back to the drains for subsequent discharge into the Marina Reservoir via the new diversion canal.

PUB said these solutions were identified after a nine-month study to look for long term measures to strengthen flood protection for the Stamford Canal catchment.

"The construction of a new diversion canal will divert stormwater from about 240 hectares, or 38%, of the Stamford Canal catchment to Singapore River. Complementing the diversion canal is a detention tank which will be built to capture excess stormwater from the existing drains along Holland Road. These measures will enhance drainage capacity for this upstream area and protect it against more intense storms," said PUB.

"Instead of flowing into the Stamford Canal, stormwater at the upstream catchment will drain into the new diversion canal and flow towards Singapore River. This leaves the existing Stamford Canal to serve a smaller catchment size, and therefore allows it to better protect against more intense storms like those experienced in 2010 and 2011," it added.

“With increasing urbanisation and weather uncertainties, PUB recognises that there is a need to provide more protection for the Stamford Canal Catchment. While wanting to provide maximum flood protection, we also had to take into consideration the issues of cost and feasibility of solutions. PUB is embarking on these two solutions after carefully considering all other options and consulting with other agencies,” said Mr Tan Nguan Sen, PUB’s Director of Catchment and Waterways.