SINGAPORE - The Land Transport Authority (LTA) will be calling a tender on Friday (June 2) to install an additional 10km of railway noise barriers at 20 new locations on the North-South and East-West Lines.

The affected tracks stretch from Pasir Ris to Tanah Merah MRT stations in the east, and Jurong East to Bishan stations on the North-South line.

In the west, barriers will be erected between Redhill and Queenstown, Commonwealth and Buona Vista, and Clementi and Jurong East stations.

This is the second phase of the railway noise barriers programme, and LTA targets to award the tender by the third quarter of this year.

Following design and off-site fabrication works, on-site installation is expected to begin from mid-2018, and would be completed by 2020.

When completed, the noise barriers are expected to reduce railway noise levels by 5 to 10 decibels, LTA said.

LTA has already completed installing about 8.5km of railway noise barriers at 16 locations across the island in end-2016.

Installation works of another 3km of barriers, along nine other locations, are ongoing and expected to complete by 2018.

The installation of the railway noise barriers is a complex process which involves extensive retrofitting of existing railway structures. LTA therefore prioritises stretches along elevated railway tracks where noise levels exceed the National Environment Agency's recommended guideline of 67 decibels averaged over an hour.

LTA has also been working with train manufacturers and operators to mitigate railway noise in other ways.

These include fitting trains with noise-dampening wheels, using ballast and concrete sleepers on the tracks enabling better absorption of noise, and servicing the train wheels and tracks more frequently, it said.