25th birthday for Orwell Bridge

IT was a marvel of modern engineering, and a feat that has stood the test of time. Monday will bring the 25th anniversary of the day the Orwell Bridge opened, so today feature writer JAMES MARSTON looks at the legacy of one of Suffolk's most loved landmarks.

YOU can't fail to be impressed.

By anyone's standards the Orwell Bridge is a stunning structure. Spanning the estuary, the 190-metre bridge seems to slide across the landscape with almost effortless ease.

At the time of its construction, it was the longest pre-stressed concrete span in use. The bridge is strong enough to carry three lanes of traffic in each direction.

Now it carries thousands of us every day and has become a much-used and much-loved landmark.

Construction of the bridge began back in October 1979 and was completed in December 1982 to carry the then A45 over the Rover Orwell just south of Ipswich.

Ipswich by-pass, including Orwell Bridge, took ten years from inception to completion.

It cost £24million and the main span was constructed by using a balanced cantilever technique, casting sections on alternating sides of the pier in a weekly cycle.

The bridge is constructed of a pair of continuous concrete box girders with expansion joints that allow for expansion and contraction. The girders are hollow, allowing for easier inspection, as well as providing access for services including telecom, power and a 711mm water main from the nearby Alton Water reservoir.

Today the bridge carries nearly 60,000 vehicles a day.

The necessary inspections still cause major disruption to traffic every six years and during the last inspection in the summer of 2005 the delays caused by lane closures and speed restrictions added between 30 to 60 minutes to journey times during the peak commuting periods.

The bridge also has to be closed to high-sided vehicles once or twice a year during severe storm conditions.

Ipswich architect Roger Gilles said the bridge is a magnificent piece of architecture and civil engineering. He said: “The bridge is in fact two concrete bridges with a tiny gap between them. One carriage way is one bridge and the other carriage way another bridge.

“The bridge is extremely simple and it really is an extremely elegant structure. It is very minimalist in its approach.”

The design took into consideration the impact on the Orwell Estuary, as well as the needs of the Port of Ipswich. The bridge was set at an angle to the river to get the best relationship to the surrounding terrain.

Mr Gilles, a partner in Barefoot and Gilles, in Princes Street, said: “The bridge sits in very well with the scenery. The rising and falling of the bridge compliments well the rise and fall of the East Anglian countryside.”

The location close to the southern edge of the town was chosen to be convenient for the industrial areas of the West Bank Terminal and Ransomes Industrial Estate on the eastern end.

The air draft of the central span was chosen to be as low as possible without adversely affecting port operations. Although its has been claimed the resulting hump affects visibility and road safety, there have not been enough incidents causing injury for the Highways Agency to identify it for greater detailed investigation and possible amendments.

Mr Gilles said: “Everybody uses the Orwell Bridge. It won a number of awards when it was built and it remains a structure that turns heads.

“Rather like the Millau viaduct in France, the Orwell Bridge uses simplicity of design, and beauty of proportion. It is an amazing feat of engineering and adds a great deal of drama and dynamism to the Orwell Estuary. It's something we should be very proud of.”

Do you love the Orwell Bridge? Were you involved in its construction? Write to Your Letters, Evening Star, 30 Lower Brook Street, Ipswich, IP4 1AN or e-mail eveningstarletters@eveningstar.co.uk

1,287m is the total length from Wherstead to the site of the former Ipswich Airport

40m deep go the pilings which were sunk into the river bed

£500,000 per year to maintain

44,000 concrete “tripod” blocks were placed around the pier bases, instead of rock which is not available locally

190 metres is the span of the bridge

24m wide and 16 storeys high

19 sets of supports, generally carrying sections of 59m.

600mm is the amount the bridge deck expands by (2ft), at each end between cold winter and hot summer extremes of temperature.

On December 17, 1982, crowds of people turned out see the Orwell Bridge opened.

Eddie Sparling from Lanercost Way in Ipswich ran in the half marathon which marked the occasion, and has enjoyed the view of the bridge from his house ever since.

He said: “The marathon started on the Nacton side of the bridge across to Wherstead and back again.

I remember the sun was shining, but it was a very cold day. There was a good atmosphere and a real sense of occasion.

“My wife Audrey was pushing our daughter Claire in the pushchair that day, and today Claire is pushing her own daughter Lexie in a pushchair so we're a whole generation on!

“We had a view across Bourne Park of the bridge being constructed, and it was interesting to see them putting up the concrete pillars one by one, and seeing them eventually join up. It was also interesting to see the curve - as most bridges were just straight.

“At the time there was divided opinion at the bridge's design, in fact come people called it a 'concrete monstrosity' but there is no doubt that in practical terms it made a tremendous difference particularly in saving lorries going through town. We know what gridlock it causes when traffic is diverted off the bridge to come through town today.”

Eddie, 63, added: “The more you see the bridge the more you realise that particularly with the curve, it has blended into the background and is beautiful in its own right.

“At this time of year we see the sun rise underneath the bridge's arches, and it appears to sit on the top. The colours can be fantastic.”