200km of new water pipes to be laid in next 13 years

200km of new water pipes to be laid in next 13 years
Workers are seen carrying out pipe-jacking at a work site at Punggol Way on May 17, 2017. Photo: Wee Teck Hian/TODAY

200km of new water pipes to be laid in next 13 years

Costlier method being used to preserve structures, bypass existing infrastructure

SINGAPORE — To meet the growing demand for water, Singapore will lay 200km of new pipes over the next 13 years, and it is getting costlier to do this.

This is part of the reason for the increase in water prices announced in February.

Water prices, the Government has said, will go up by 30 per cent in two phases, from this July.

Given that land is scarce and built-up space is expanding, the authorities have been turning to pipe-jacking to lay pipes, in order to preserve structures and bypass existing infrastructure, such as train tunnels.

And “the best way” to do this is to “go below them and deep under them”, Minister for the Environment and Water Resources Masagos Zulkifli told reporters during a visit to the pipe-jacking worksite at Tanglin Halt yesterday. As it is, 90 per cent of current projects use this method for certain sections of the pipelines.

Pipe-jacking costs 2.5 times more than the conventional open-cut method, and this adds to the cost of managing and operating Singapore’s water system.

The process involves lowering a hydraulic jacking machine and pipe into a shaft at one end, before the pipes are pushed into position underground.

Once the pipes are laid, the jacking machine is removed from the shaft at the other end. This is also slower than the conventional method, where trenches are dug to lay the water pipes underground.

With the need to use pipe-jacking, Mr Masagos said that it was necessary for the authorities to properly budget for such costs.

“It is within our budget, but we have to ensure that we have enough to recover from our operations to fund this project for the next 15 to 20 years.”

The use of pipe-jacking is not new. It has been used in pipeline projects at Telok Blangah Green-Henderson Road and Choa Chu Kang.

For each of the ongoing pipeline projects, 10 to 85 per cent of the work can be done using pipe-jacking. For instance, about 85 per cent of the new 4km-water pipeline from Punggol Way to Sungei Serangoon will be installed using the pipe-jacking method. This is to meet future water demand in the eastern part of Singapore.

At the Murnane Service Reservoir in central Singapore, work has begun to lay a new 22km pipeline — which starts from the reservoir and stretches till Maxwell Road — to meet future water needs in the city area. About 40 per cent of the project will also use the pipe-jacking method. Work is expected to be completed by the end of 2019.

Over the next two years, national water agency PUB will lay 60km of new pipelines to meet demand from new developments, and 75km of the older pipelines will become due for network maintenance and improvement work. PUB manages about 5,500km of potable water pipes, which is about the distance from Singapore to Osaka, Japan.