Wednesday, November 18, 2015

The Wonderful Rotherhithe Bascule Bridges

Surrey Basin bascule bridge by Rob Noble
Two of Rotherhithe's most distinctive landmarks are its wonderful Scherzer bascule bridges.  Neither of the bridges are functional now, and they have been stripped of their associated paraphernalia, but both are quite remarkable.  Today they are painted red, and look marvellous. Their scale is best appreciated when you stand beneath them - they are truly massive.  One of them crosses the underpass that leads from Greenland Dock to the shopping centre at Canada Water, next to Salter Road, and the other crosses the Surrey Entrance Lock on the opposite site of Rotherhithe, near the Old Salt Quay public house, where it forms a part of Rotherhithe Street.  Although they are very similar, they are not identical.  You can compare them in the photographs below.

Image from Wikipedia - I love it! Every
time I see it, I think that the little car on
the right is going to fall straight in!
http://bit.ly/1SWQY0P
Bascule is the French word for a seesaw or balance. The best know British bascule bridge is Tower Bridge, a rather more massive undertaking than the Rotherhithe one, with two leaves, but following the same principles. Scherzer bascule bridges are lift bridges that roll or rock back on a curved base to rise so that ships can pass beneath, and are often compared to Medieval draw-bridges. They may have one leaf, like the Rotherhithe ones, or two leaves, which open either side of a span and meet in the middle (like Tower Bridge). Scherzer bridges are found all over the world because they have simple mechanisms, open rapidly and have low energy requirements. The bridges consist  of two important components - the length spanning the gap, in the Rotherhithe cases spanning two sections of road, and a counterweight filled with water. It sits on tracks, and electric motors wind the bridge over the tracks with the assistance of cogs and racks that fix it into place at 90 degrees to prevent slippage. They must have been quite something to see when they were working.  In spite of its somewhat Victorian look and engineering here in Rotherhithe and at various other locations in the United Kingdom, the bridge was such a success that it continues, now that the patent has expired, to be a successful engineering solution
 
From HistoricBridges.org
http://bit.ly/1SXTNid
When I first saw them I thought that they probably dated to the late 1800s or early 1900s, because have so much Victorian panache about them.  In fact one was built in the late 1930s and the other was added in 1949, having been moved from Deptford.  But it turns out that I wasn't far from the mark.  The bridges were built to a design by William Donald Scherzer of Chicago, who patented the design in 1893.  Following his death in 1893 the business was taken over by William's younger brother Albert Scherzer and the company successfully preserved its exclusive patented rights to build this particular style of rolling bascule bridge for decades afterwards.  There is a brilliant description of the development of the Scherzer bridge in Chicago in this early 1900s pamphlet by the Scherzer Rolling Lift Bridge Company:
Starting at a time when engineering in this particular branch of the science was entirely undeveloped and there was little upon which to base our designs, except theory and unbounded faith, we have now the satisfaction of having proven both our theories and our faith, the Scherzer Rolling Lift Bridge being today universally known as the standard of excellence in bascule bridge design, after a period in modern structural engineering in which the development of the bascule bridge has been one of the noteworthy features. 
It is a basic principle of all great inventions that necessity is the stimulus, and a brief outline of how history repeated itself and necessity brought out the Scherzer Rolling Lift Bridge is interesting. The Metropolitan West Side Elevated Railroad of Chicago had practically completed all of its other construction without solving the serious problem of earning its tracks over the Chicago River where the limited right of way between the swing bridges at Jackson Boulevard and Van Buren Street precluded the use of a horizontally moving bridge of the required span length, time and money were expended freely in consultation with the most eminent engineers in the country and various solution  were suggested, each, however, developing limitations that made them impractical. Vertically moving bridges in all of the varieties as then known even to a reproduction of the new Tower bridge across the Thames in London were proposed but none was satisfactory in meeting all of the requirements. The management called in William Scherzer of Chicago, a consulting engineer specializing in structural design, and it was his ingenious but practical suggestion that both solved the problem for the railroad and to the science of movable bridge engineering its most important development. It is the irony of fate, too, that death from over-work in concentrating on this very matter should have robbed William Scherzer of the satisfaction of seeing the completion of the structure to which he had given so much of his time and thought, but credit will be given to his name wherever the history of movable bridge engineering shall be written.


Surrey Basin bascule bridge in the 1950s and
2004. From Rankin's Walk A, p.24
At the time of the installation of the bascule bridges in Rotherhithe there were only two ways to leave Rotherhithe by road, and when both bridges were up at the same time, the peninsula became an island and all traffic came to a standstill for as long as it took for ships and smaller vessels to pass.  The sense of being at the mercy of the bridges is captured by the title of F. Mary Wilson's 1960s book Between Bridgers. She says that awaiting the bridger is "a local phrase for the cessation of traffic and pedestrians." Another phrase was catching a bridger, which was used to indicate that someone had been delayed by the raising of the bridge or bridges. Much better than "the dog ate my homework."  The local Rotherhithe fire brigade, at that time located between the two bridges, were not permitted to cross over either in case the fire engines should become trapped on the wrong side of them when the bridges were raised, which would have prevented the engines returning to service in the main Surrey Commercial Docks area in an emergency.  The bridges were also known locally as "the iron bridges."

In London, as in other parts of the UK, the 1930s are known as a period of economic depression, followed immediately by the Second World War. The majority of people working in and around Rotherhithe in the 1930s were working-class families, dock and river workers, struggling with the economic conditions, but there was a brief book in the timber trade and Rotherhithe was one of the principal timber handling dock systems at that time.  In response, the Port of London Authority (PLA) did much to upgrade the docks at this time to improve their prospects, including open-sided timber sheds (principally for the newly desirable plywood), a new general cargo warehouse of 75,000sq ft, and two small timber ponds were amalgamated to form Quebec Dock.  The two bascule bridges were part of this programme of improvement.

Surrey Basin bascule bridge
The Surrey Basin bascule bridge is still in its original position over the lock between the Thames and the Surrey Basin (now known as Surrey Water) next to the Old Salt Quay public house. It replaced a somewhat elderly swing bridge, of which there were several around Rotherhithe, thanks to the crazy mosaic that made up the Surrey Commercial  Docks. The lock is Grade 2 listed (IoE Number: 471266) but the bridge does not appear to be listed. It is Rotherhithe's oldest bascule bridge, 20m long and was built to cross the lock into Surrey Basin, which in turn led into the Surrey Commercial Dock network.  As the smallest of the available locks connecting the docks to the Thames (the biggest lock was the one into Greenland), it mainly handled smaller ships and barges, but was still a very important access point.  The photograph taken shortly after its installation (see above) shows a corrugated iron hut built onto an overhead gantry.  This was the station from which the bridge was operated.  When I first moved into the area it was still possible to drive across it, but it was eventually decided to convert it to pedestrian-only access, which was an excellent decision.  It is a great place to go and have a quiet look at the construction.  The Shadwell Basin bascule bridge (on the north of the Thames) is very similar to Surrey Water bridge, and as both were operated by the Port of London Authority they were probably sourced from the same manufacturer.  The Shadwell bridge was erected during the 1930s by the successful engineering contractors Sir William Arrol and Co., which specialized in rolling lift bridges during the 1930s.  Although the company's origins were in iron working, it became well known for its excellence in steel working, and this skill was used in its build of Southwark Bridge.   The Surrey Basin bridge in articular looks like another Sir William Arrol and Co. bridge, the White Cart Bridge in Glasgow

Greenland Dock bascule bridge
The Greenland Dock bridge that carried Redriff Road over the cut between Greenland Dock and Canada Dock was built in 1949, when it was erected in Deptford to bridge the Deptford Creek.  Ten years later it was moved to Rotherhithe to replace an ageing swing bridge, which had been erected when the cut between the two docks was made in 1904.  It is of a different construction to the Surrey Basin and Shadwell Basin examples, without the extensive metalwork on either side of the roadway.  Instead the water tank is connected directly to the sides of the bridge, with no metalwork above it.  As the Deptford Creek did not come under the authority of the PLA, it is possible that the Greenland Dock bridge could have been made by a different manufacturer. Today the bascule bridge no longer carries the road but sits parallel to it, and is easy to visit and inspect.

It is strange to think that only twenty years later the last ship was leaving Greenland Dock, and that the last wharves closed in the 1980s, but even when the bridges were erected the writing was firmly on the wall.  Stuart Rankin calls the post-war period "a false dawn."  The bascule bridges, so vast and confident, are an admirable monument to both engineering excellence and a complex economic and social past.

Thanks to @RainbowQuay for letting me know that a YouTube video of the Surrey Basin bridge operating, that I knew existed but couldn't find, is now at the following address (and just look at all those umbrellas!):
https://www.youtube.com/watch?v=a-G0TgiAljg

The Shadwell Basin bascule bridge, which is
no longer operational. (Shadwell Wikipedia page)



References:

I had the devil's own time finding information about these bridges, so in addition to those credited in the text and captions, my thanks to the following books and sites for information to start me off:

Stuart Rankin, Rotherhithe History Walk A (Southwark Council 2005)
F. Mary Wilson, Between Bridgers (no publisher, late 1960s)
Stuart Rankin, A Short History of the Surrey Commercial Docks, Rotherhithe Local History Paper 6, 1999.
The Adam Hunter pages on www.engineering-timelines.com
Historic Bridges www.historicbridges.org
Archive.org http://bit.ly/1MmZ8x

Photos of other European and American bascule bridges are on Wikipedia:
https://en.wikipedia.org/wiki/Bascule_bridge




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