Sutton Weaver Swing Bridge (photo heavy)

[davel]

I was lucky enough to have Canal and River Trust lay on an open day at Sutton Weaver Swing Bridge on my birthday - here is a bit of background information.

 

Sutton Weaver Swing Bridge carries the A56 over the River Weaver Navigation, built in 1926 to replace the original bridge built in 1872 which was 75' long by 14'wide, weighed 20 tons and was manually operated by one man.

 

By 1923 it could no longer cope with 'modern' traffic.

 

The present bridge is 150' long by 44' wide giving a clear roadway of 26'8" plus two footpaths of 5' and is operated by electric motors. The swinging section and the pontoon it sits weigh about 520 tons including 420 tons of iron and steel. The pontoon weighs about 33 tons and is 35' in diameter and sits in a water filled caisson.

 

The pontoon is hollow and functions by displacing water equal to the volume of air in the pontoon reducing the weight borne by the rollers it turns on by about 200 tons.

 

When being swung road traffic was stopped by heavy iron gates hung on ball bearings and connected by underground gearing. These gates are still in situ but are not used. Road lighting on the bridge was electric but the red and green signal lamps were paraffin.

 

Canal and Rivers Trust are refurbishing and upgrading the bridge in a 12 month £4.5 million project, £3/4 million of which is for a temporary bridge to avoid major disruption of traffic and to enable the contractors to work on the bridge as a whole rather than have traffic on one side at a time and working on the other side thereby offsetting more than the cost of the temporary bridge.

 

Sutton Weaver Bridge (photo from a wikicommons)

 

 

The winding gear under the control room -

 

 

- driven by this 30bhp drive motor

 

 

The cable runs in this channel to the pontoon

 

 

The PA system in the control room is outside the scope of the refurbishment.

 

 

The original 1926 controls for operating bridge which work more reliably than many modern controls so the decision was made not to upgrade them. If it ain't broke don't fix it.

 

 

My glamourous assistant (in full PPE) demonstrating the controls.

 

 

The control room.

 

 

The horizontal rail through the centre of the picture has completely rusted through at the left of the photo.

 

 

Sand blasted and painted vs not sand blasted and painted.

 

 

Original decking. If you jump on this, water squirts out of the holes.

 

 

The pontoon does not sit exactly in the centre of the bridge so this cavity under the road deck contained about 80 ton of counterweights (or counterlage as the engineer called it) consisting of -

 

- these ingots. The new decking is lighter than the old but they are not sure by how much. They weighed each end of the bridge at the beginning of the project and will replace enough weight to match the original proportions.

 

Refurbished lattice work

 

More photos to follow ...

Edited February 11, 2014 by davel

[matty40s]

Bloody great Birthday Pressie, no wonder you need a mooring, you would never fit that bridge on Ionas roof..

[davel]

Unrefurbished.


Refurbished.


Original road deck awaiting replacement.


The engineer thought this is damage from a vehicle crashing into it.


Sand blasted and primered.


1 1/2" clearance gap between bridge and road.


When the bridge was swung these gates were used to stop the traffic. They are not used now but will be repainted to preserve them.


The gate turns on this post on ball bearings.


Some of the spikes have completely rusted away.


New railings awaiting installation.


New decking. I think you're gonna need a bigger hole punch.


Section of old decking.


Section of old railing.


New lattice components.

Bloody great Birthday Pressie, no wonder you need a mooring, you would never fit that bridge on Ionas roof..

ROFPMSL

[junior]

Great pictures. Did they do you a cake?

[Ange]

Great pictures. Did they do you a cake?

Dave's laying down recuperating after spending an hour on his post

 

They laid on coffee and biscuits but no cake

[Derek R.]

Fantastic stuff! But needs cake . . .

[Pluto]

These are the Hayhurst Bridge floating pontoons during refurbishment in 1977.

 

The following is from a report I wrote on the Northwich swing bridges in 2003:

 

A major problem with the site for the bridges was the effect of subsidence. To overcome this, bridges in which the majority of their weight was supported by pontoons were envisaged from the start, though plans for bridges with conventional foundations were also drawn up. These later were used for the application to Parliament for an Act in 1893. In this, Town Bridge was located on the northern river bank, the location where it was subsequently built. Navigation (or Hayhurst) Bridge was originally designed to sit on a pier erected in the middle of the river, with navigation passages on either side. At this time, the majority of traffic on the river was downstream from Northwich, with fewer boats serving Winsford, so the difficulties of passing the pier would not have been considered so important.

However, Saner was also looking into the possibility of 'floating' bridges. In November 1892, the consulting engineer John J. Webster had looked at the project, and reported favourably on the idea. James Price, who was the Dublin Harbour Engineer who had built two swing bridges with pontoons over Spencer Dock in 1873, was also contacted concerning the possibility of his giving evidence during the passage of the Bill through Parliament. A trial swing bridge which used a pontoon was built at Weston Marsh in 1893. The final decision to use pontoons at Northwich, with both bridges being located on the river's north bank, seems to have been taken during the final stages of design around 1897. It was probably at this time that the use of electric power was decided upon, earlier plans seem to have proposed the use of hydraulic machinery for turning the bridges. Electric power for swing bridges had been used in America, but this was the first such use in Britain. Electricity was provided from the local Northwich supply at 440 volt DC, and accumulators were probably provided to ensure power in an emergency.

Both bridges were in operation by 1900, and continued in use without major repairs until 1924. Town Bridge was turned approximately ten times per day over this period, Hayhurst Bridge only being turned on average two and a half times per day in the same period. This was probably because it had greater headway, so many boats, particularly when loaded, could pass underneath.

In 1924, Town Bridge had to be raised to cope with subsidence which was causing problems with electrical machinery, as well as flooding in the town. Three years later, part of the bridge deck failed and a further closure was necessary for repairs and strengthening. Both closures caused considerable criticism from traders and other local people, particularly as the Dane bridge also needed improvement. The deck of Hayhurst Bridge also failed in 1933, and this too had to be closed for strengthening.

The Northwich bridges reconstruction at this time was of national importance in that it raised the question of whether canal bridge improvement to cope with modern traffic requirements was the responsibility of the navigation authority, the local authority or the Ministry of Transport. Settling the funding was one of the main causes of delay in reopening the bridges, and questions were asked in the Houses of Parliament.

[David Mack]

The pontoon does not sit exactly in the centre of the bridge so this cavity under the road deck contained about 80 ton of counterweights (or counterlage as the engineer called it)

 

I suspect he said kentledge.

[Richard T]

Great to see you posting instead of your missus, What a great birthday present.

[nebulae]

How will traffic be controlled in the future? Am i right in remembering that the origional gates were opperated by man power?. Will there be some sort of automatic barrier in future?Given the clearance under the bridge,how many times is it likely to swing in the future?Always good to see these old structures still able to function.No doubt there will be winging from local motorists as in greater use of Ship Canal bridges.

[davel]

 

I suspect he said kentledge.

Thanks for the correct term David, I asked the engineer to repeat it twice and was then too embarrassed to get him to spell it for me. I tried googling Cantiledge as in Cantilever and Counterledge as in Counterweight but was stumped after that.

 

How will traffic be controlled in the future? Am i right in remembering that the origional gates were opperated by man power?. Will there be some sort of automatic barrier in future?Given the clearance under the bridge,how many times is it likely to swing in the future?Always good to see these old structures still able to function.No doubt there will be winging from local motorists as in greater use of Ship Canal bridges.

The gates appear not to have been used for a number of years, the present system is the same as at railway crossings with flashing red lights, audible alarm and a dropping barrier.

 

edited for dodgy punctuation

Edited February 15, 2014 by davel