Newport's newest bridge, forming part of the SDR, is a magnificent sight, spanning the River Usk.

And as the final stages of construction were reached engineers found they had their calculations almost spot on and the two sides of the bridge were a mere three inches apart.

The operation, which took place in late summer 2003, has come to light under questions posed by the Argus under the new Freedom of Information Act.

Details show contractors built the roadway of the bridge by pushing its two halves out from either bank of the river Usk and when they met specialist engineers found one side of the bridge was just three to four inches higher than the other.

The team then used a massive jack to raise the lower side until it met the other half.

The two parts of the metal bridge, which had no surfacing at this stage, were then fixed together.

Peter Frood, project manager of the SDR for contractors Morgan Vinci, said: "Each of the two halves was 92 metres long and they were pushing out 750 tonnes of material.

"It was a very specialist operation that was carried out by engineers from Fairfield Mabey.

"They built in deflections and calculations so that the bridge could be adjusted to enable it fit together."

Brian Kemp, head of engineering and construction at Newport council, said that once the bridge had been aligned concrete decking and tarmac went on top. The £55m Southern Distributor Road has cut congestion in Spytty and Corporation Road.

The Argus announced the bowstring bridge, opened to vehicles in late November, will be called City Bridge. The opening of the SDR was delayed from its predicted opening of June 2004 due to problems with drainage, barriers and sinkage.