SINGAPORE - Or Kim Peow, the local construction firm whose viaduct project in Changi came to a halt on Friday (July 14) when part of the raised road it was building collapsed, had submitted the lowest bid to secure the contract in 2015.

According to tender documents, OKP - which partnered engineering consultancy CPG to land the deal - had put in a bid of $94.6 million.

This was 27 per cent lower than the next lowest bid of $129.7 million by Yongnam Engineering.

Two other bidders - Singapore Piling and Samwoh Corp - had submitted bids of $185.0 million and $193.7 million, respectively.

These were double and more than double what OKP's winning bid was.

Despite the two-envelope system - which is supposed to prioritise quality over value - public projects still tend to be awarded to the lowest bidder.

One worker was killed in the viaduct collapse, and 10 others injured - two seriously on Friday.

Preliminary investigations found that concrete supports of a section being cast had given way.

Work had been halted at the site, and the incident - which also blocked off a sliproad - may be delayed.

The viaduct was scheduled to be completed in early-2020.