FLYOVER AT WOODSVILLE INTERCHANGE (Collapse of concrete beam)

Dr Chau Sik Ting asked the Minister for National Development, in view of the near disaster arising from the recent collapse of a concrete beam of the partially completed flyover at the Upper Serangoon Road/Jalan Toa Payoh junction, what steps have been taken to ensure non-recurrence of similar incidents elsewhere.

Mr Lee Yock Suan (for the Minister for National Development): Sir, on 26th September, 1981, one of the 99 precast beams at the Woodsville Interchange construction site, which was lifted into place three days earlier, was dislodged from its seating. It overturned and fell onto the road below. Investigations show that the flyover was structurally sound and the beam was properly designed and manufactured. It fell because the temporary supporting wedges used by the contractor had apparently been knocked out of place by workmen engaged in other work nearby. The contractor has admitted full liability for the incident. Immediate steps were taken to check the tightness of the wedges for the other beams. Additional safety measures, including temporary ties and weldings to interconnect the beams, were taken to enhance the stability of the beams pending the construction of the bridge deck which will ultimately connect them together. These additional measures have fully secured the beams against overturning.

Immediately following the incident, a technical review was conducted on the stability condition of all other precast beam construction projects in progress. These include the flyovers at Paya Lebar Way, Aljunied Road, and various pedestrian overhead bridges. Their design and erection procedures were all found to be safe.

The PWD will in future require all contractors to adopt erection procedures with two or more independent safety systems. This will provide additional back-up safety measures to prevent a recurrence of similar incidents.

Dr Chau Sik Ting: Sir, this is a very grave matter. It concerns public safety. First, can the Minister assure the House that contractors are selected on a basis of proven experience and track record on safety? Secondly, will the PWD in future cordon off the affected roads for these projects until the structures are certified to be safely secured?

Mr Lee Yock Suan: Sir, the answer to the first question is "Yes". The contractors who were involved in the previous projects involving similar incidents were all large and experienced contractors. The answer to the second question is that there is no necessity to cordon off the area because adequate safety measures will be taken. As I have explained in answer to the original question, the PWD will in future require all contractors to adopt procedures with two or more independent safety systems.

Encik Saidi Haji Shariff: Sir, I just want to ask the Minister of State whether the measures he has mentioned are based on the findings of whatever inquiry he has conducted to determine the cause for the collapse of the flyover at Jalan Eunos in 1979, and whether these findings have been released?

Mr Lee Yock Suan: Sir, I do not have the facts at hand to answer the question. If the Member will allow me, I will ask my Ministry to supply him with a written answer.