Report of the 35th Annual General Meeting
by Bill King
The usual crew were already at the Brentwood Theatre when I arrived. Everyone was happy that Geoff was able to present the Harry Jones Award to John Watling for his article "Carriage Building in 1907 and the Norfolk Coast Express".
The primary interest of the day was, however, the traditional talks which accompany the AGM.
The Reconstruction of Trowse Swing Bridge by Martin Fargher
Martin Fargher kicked off with his presentation on the reconstruction of Trowse Swing Bridge in 1987. See also here and here.
He explained that before his appointment as Resident Engineer at Trowse, he had been responsible for the infill of a large bridge which accommodated Leeds station as it passed over a redundant arm of the Leeds & Liverpool Canal.
The arrangement of the new Trowse bridge relative to the old was made clear in GERS News 53 (see map above), together with the project brief:
- To avoid traffic disruption the new bridge would be built on a new alignment upstream of the then existing bridge
- As a consequence of the deviation, an Act of Parliament would be required to enable its construction
- The bridge would accommodate a single line of track
- The bridge would be brought into service at around the same time as the Ipswich - Norwich electrification was commissioned
- Although the 25kV overhead supply would only be energised when the bridge was open for rail traffic, the provision of such a system made it unique
- The joints between the swinging spans and the fixed part of the bridge would be arranged to provide an overlapping rail joint
- The project was estimated to cost £3.953m
- On completion the old bridge would be removed
This is the third railway bridge to cross the River Wensum on the approach to Norwich. The first was built to carry the Eastern Counties Railway line into the Thorpe terminus and opened in December 1845. The second was of double track configuration in an effort to reduce the traffic bottle-neck created by the previous single track span.
The new bridge differed from the two previous versions in a number of technical details:
- The pivot was not arranged at the centre of the swinging section, the length of the two spans about the pivot being 30m and 6m
- The bridge does not rest on the pivot when it is open to rail traffic. As a consequence, the pivot can be of relatively light weight construction
- A method was required to raise the pivot into contact with the swing spans and then further raise the complete assembly prior to pivoting. The method selected was to utilise four hydraulically driven screw jacks
- The need for a complicated system of wedges to align the remote ends of the swinging spans with the fixed was avoided, with the bridge being simply supported on plain bearings at its ends
- The "catenary" across the bridge is replaced by a rigid beam with a slot in its bottom face to hold a conventional conductor wire
Martin's first task at the site was to supervise the construction of a bank of ducts under the river through which the 25kV power supply cables and signalling and telecommunication cables pass to the remote side. The British Railways (Trowse Bridge) Bill was introduced into the 1984-85 session of Parliament and, once Royal Assent was received on 22nd July 1985, work could begin in earnest.
The construction of the new bridge was contracted to the local company May Gurney with the electrical and hydraulic systems and bridge structural steelwork being sub-contracted to Butterley Engineering. The bridge fabrication was undertaken by Butterley in their works at Ripley in Derbyshire.
A class 31 diesel locomotive 31.417 was the first rail vehicle to pass onto the bridge on 11th February 1987 and was used to compress the waybeams to allow tightening of their fastening - we saw a view of it undertaking that duty. Final commissioning took place over the weekend of 14th - 15th February 1987. During construction Trowse Swing Bridge Junction Signal Box was eliminated, but a swing bridge control room was built on the opposite river bank.
During the 20 years since the bridge was brought into service the opportunity has been taken to update the bridge lifting system, now utilising a hydraulic primary system:
- Improvements in hydraulic control technology now permit the synchronisation of multiple hydraulic jacks operating in unison
- The mechanical screw jacks were found to not respond satisfactorily to an applied off centre load
Originally, the bridge was required to open on demand. Indeed, the Act of Parliament required it to be so. This was found to be altogether too disruptive to rail services and the bridge is now available to open four times each day at stated times.
This was a fascinating talk with bags of technical detail by the engineer who was "at the sharp end". It was very well received by the audience who responded in the usual way.
The Sweedie by Iain Scotchman
After the AGM, Iain Scotchman provided us with an unusual "virtual journey" from Norwich to Liverpool Street. It was in the blue diesel era and copiously illustrated with Iain's own slides.
"The Sweedie" was the story of the 10.32 departure from platform 2 at Norwich Thorpe in 1979 or 1980. Arrival at Liverpool Street was due at 12.43. It was hauled on this day by 47.117.
Imagine that you were on this train, that Richard Ball, Passenger Operating Assistant, Liverpool Street was in the next seat and that Terry Simister, Secretary of the Society, was opposite. Sit back and let Richard and Terry describe the journey.
Leaving Thorpe, we have to climb a 1 in 84 gradient on the line towards Norwich Victoria where there is a speed restriction of 40mph. The gradient gives the lie to the old belief that East Anglia is flat. There was not much custom and the lines had steep gradients and tight curves. East Anglia was primarily a barley-growing region, much grain was shipped to the mills and breweries in London.
Passing Tivetshall, the junction for the Waveney Valley line to Beccles which closed in 1966, Richard reminds us that near Pulham Market, a station on the branch, one of the first airship bases was built. Soon after this we arrive at our first stop. Listen hard and you can hear: "Diss,….Diss,…..This is Diss!"
After a short wait, we accelerate up the gradient through Mellis where there was the junction station for the Eye branch.
Travelling on, we pass Haughley Junction where the line from Bury comes in from the right. Many airfields were built in this area during World War Two, the station handling 445 trains of aviation fuel during the first six months of 1944. Coming towards us is a class 37 on a beet pulp train. This is probably destined for Scotland or the North West as animal feed.
Shortly after this, we arrive at Ipswich. Terry tells us that this was an important part of the Great Eastern where the branch to Lowestoft went off. The fishing port was railway-built and owned, fish landed here was placed into trucks marked with special red labels, conveyed along the branch to the main line and attached to the first London express. It was also the centre of a most eccentric service. Sea water could be shipped to any station on the GE system for 6d a barrel.
Meanwhile, in the buffet on our train - a good way to meet people - Chief Steward Ernest Ward is serving breakfast. Passing the plastics factory at Brantham, we cross the two bridges over the Stour to arrive at Manningtree. This is the place of the triangular junction with the Harwich branch, and important because of the Parkeston Quay ferry connections with the Continent. Unusual freight traffic originates at Mistley where industrial explosives are produced.
"This is Colchester. The train arrived at platform 3 is the 11.49 train for London only. British Rail apologise for the late running of this train." Here we are 51½ miles from the metropolis, having travelled just over 63 miles from Norwich. Leaving Colchester, we are soon passing Marks Tey where, Terry tells us, Lord Claud Hamilton once had a down express, conveying his personal carriage, especially stopped. He left the train and went into the Refreshment Bar on the platform. On rejoining the train he was asked by his companion of the reason for the out-of-course halt. "Well you see," said he, "they told me they had taken on a new barmaid here and I just had to see if the stories about her were true!"
This is the fastest stretch of the old Great Eastern main line - the line speed limit here is 100mph and we are travelling at 95 - that is the limit for this type of locomotive.
We are soon approaching Shenfield, almost 95 miles from Norwich and just 20 left to go. The line from Southend Victoria joins here.
Maurice Holmes is the manager who is based at Bishopsgate and looks after the Liverpool Street and Fenchurch Street lines. There are six tracks on the entry to the terminus, widening into 18 platform roads. Between 5 and 6 pm 144 train movements take place. Liverpool Street is not unacquainted with intense service, of course, the "Jazz" having been reckoned to be the most intense in the world. As John Betjeman remarked about the "county" and business passengers arriving at Liverpool Street: "The ladies go second class, most of the men go first, except of course the vicars."
The station was built on the cathedral plan, with nave, aisle and transept - at this time, the redevelopment plans for the station are just being formulated and there is a campaign to retain as many of the existing buildings as possible. And so we arrive at our destination. No longer should this line be called "The Sweedie". It has an important function as a passenger railway, conveying boat train and other "customers" and now handles Ford motor cars and oil traffic. Well done Iain, who had reproduced this journey of almost 30 years ago using the latest technology. He was warmly congratulated with a round of applause.
And so, yet another visit to Brentwood was over - the crowd made its weary but contented way home. Dave Zelly tells me that before our next visit the Brentwood Theatre will have new dressing rooms, so best wishes to them with the building work!
Map courtesy of Iain Scotchman. The pictures of Trowse swing-bridge kindly supplied by Martin Fargher.