National water agency PUB's letter, "PUB replaces old drain gratings progressively" (Oct 1), said drain gratings are being replaced in accordance with the latest design and standards, revised by the Land Transport Authority (LTA) in 2011.

The new design has grating bars which run perpendicular to traffic flow.

I noticed that steel wire mesh is also fixed on top of some gratings to prevent leaves and other objects from entering the drain.

This enhances safety for cyclists and is therefore a good design.

Unfortunately, I have also observed that in some cases, there is still a gap between the grating cover and the concrete edge of the drainage outlet.

There are many levels of checks throughout the installation process - at the construction stage, on completion before LTA takes over from the contractor, and when LTA hands it over to PUB.

But some defects seem to have slipped through the checks.

I urge PUB to check all roadside drain gratings thoroughly and rectify any defects to prevent further accidents from happening.

Good design with poor workmanship and quality control is just as bad as poor design.

Yao Chee Liew