Real problem with the Dublin St Bridge

An article in the Whanganui Chronicle on May 11 stated that the Dublin St Bridge should be replaced to improve the traffic flow.

I am a retired local body engineer with 47 years of experience with the Whanganui District Council and Opus.

The problem is not the bridge but the intersections at either end. If the intersections are improved then the two lanes of traffic is adequate ...

When I was manager of PES, the engineering business unit of the council, we had 10 different solutions in the drawer mostly for the Somme Pde intersection.

These were presented to the council but not proceeded with, mostly because of cost.

The problem is the traffic travelling in both directions on Somme Pde which does not need to interact with bridge traffic.

One solution was to lift one or two of the steel spans on the Whanganui East side, roll them across the bridge and use them to allow the straight through traffic on the parade to flow underneath.

These are currently over land and could be replaced with earth embankment.

Some will say it’s not possible but the steel railway bridge was built on top of the timber structure then lowered into position.

Alternatively a separate structure could be built to achieve the same thing in separating the traffic and reducing conflict.

Many years ago when old houses occupied the site where the motel is now the then council lost the opportunity to buy this land and expand the intersection.

The solution will need some land take to get a much larger roundabout [but] this will need to happen anyway with a new bridge.

A complicated linked traffic signal system could be installed. This will not improve overall traffic flow but does give everyone a fair go. JIM ENNIS Be(civil) FIPENZ

Whanganui