Bypass standards

David Sutton, acting chief executive officer and Klaus Mueller, road consultant of the Malta Transport Authority (August 18) have joined forces to rebut some of my criticism of the standards of the newly reopened St Paul's Bypass. It is not through lack of respect that I dare to reply single-handed to these two gentlemen, but a number of friends and colleagues have expressed support for my letter of August 10.

So I am not alone.

The above gentlemen have extended an invitation to me to meet their design and engineering team to discuss the technical issues in more detail. I gladly accept their invitation and await their telephone call. My criticism was meant to be constructive and it makes more sense to discuss technical matters face to face round a drawing board, rather than in the press. However, as in their otherwise acceptable letter, these gentlemen have suggested that "some readers may have been misguided by some technical assertions", I feel I owe it to these same readers to make a few very brief points before taking them up further at the proposed meeting.

Road geometry: This was largely inherited from the original design but a 50 km/hr design speed (over a stretch) sounds inconsistent on a bypass and may have been improved with adequate superelevation (banking).

Open storm water culverts: These are dangerous and unacceptable and smack of the Third World rather than the EU. They should be covered and/or protected. Safety fences: Except at particularly hazardous situations these are now discouraged. From a moving car I could not see any spring coils at the supports or elongated eyelets at the beam junctions to aid flexibility and impact absorption.

Asphalt structure adopted: A 20cm blacktop for a 3-10 msa design sounds quite acceptable and is more or less what I would have expected in the circumstances. A 250 metre stretch at 48cm sounds rather wasteful and I would take a lot of convincing that there was no cheaper alternative. The previous mention of "tarmac" seems to have been a flight of fancy of the PRO.

Wearing course: The use of basalt aggregate in the wearing course was, unfortunately, not mentioned by the PRO, and that is the most positive single aspect of the project. I have been advocating this, even on a "differential wear" principle, ever since I can remember.

Viewpoint: The floating oilrig seems to have moved off and St Paul's Island can now be seen in all its glory!