“I’ve got an interesting project for you to look at…” – these words fill me with dread, excitement and the thought of yet another challenge to overcome. Really, I have no idea why we get these calls, but I am so glad we do.
The client explained the situation. Basically, they needed advice on how to clean and bird proof the lifting mechanism for a vertical lift bridge on the Teignmouth to Shaldon Road Bridge in Devon. The bridge has not been lifted for 50 or so years and as this is a Heritage Site, plans were in place to renovate the workings and get this operational once more.
So off I went to Devon to take a look. Access to the chamber under the road was via a manhole, down to a platform and then inside the chamber – a monster of a void under the road measuring approx. 12mt x 6mt and very deep – around 6mt from the doorway.
Safety is our prime consideration when on any site, but with this unusual access arrangement, and the potential of dangerous gasses inside the chamber, we provided safety hoists and gas detectors to eliminate the potential hazards.
There were in excess of 300 pigeons staring straight back at me when I put a torch on, so this was going to be a major project, just in moving out all these birds. Anyway, the rest of the survey was carried out and proposal submitted accordingly, including the bird prevention measures and the use of an under-bridge cherry picker to access the areas where the mesh prevention was to be installed as this was over the river estuary….but then the bad weather struck Devon, destroying most of the coastline in the process, calling this project to a halt.
18 months passed, then the call came to resurrect the project, but with a few changes, requiring a further site visit to clarify the amended requirement. Basically, a local bird protection group were used to remove the pigeons and attempt to stop birds re-entering, a scaffold platform had been installed inside the chamber and works had started on the lifting gear inside – quite a difference to the original spec, but not a problem.
Our new scope was to replace the temporary prevention measures with a permanent bird proofing solution, clean all the pigeon fouling from all visible surfaces inside the chamber ready for the real work to begin of replacements of bearings and gears to enable the bridge to work once more. The use of a Moog 120 Cherry Picker was essential, but booking one is a bit of a challenge as there are only 2 in the UK…and both are almost permanently busy.
As it happened, the client had one of these machines booked on another job which was just finishing, so allowed us to continue the booking – but this collapsed all timeframes to get this project arranged and delivered – we had a very small window to work around but our suppliers are brilliant and soon all materials and safety equipment were arranged and ready to go – the only thing that could stop us now was the weather!
As the installation date came closer, we avidly watched the weather forecasts expecting the worst scenario, but on the first day of the project we could not have been more happy – bright clear sunny weather and very warm as well – a miracle indeed.
When you start a new site, establishing a safe working area is essential, especially on highways, so the Traffic Management team went through the plans with us and soon established a working plan to make sure the works could be started without risk to the public or us. Interestingly, the traffic flows over this bridge at rush hour matched levels found in London – I did not expect this from this sleepy town in the depths of Devon.
Once our work area was secured, we called in the MEWP driver with the Moog 120 – a massive lorry mounted beast of a machine – who had parked up the road a bit to allow us to get everything sorted.
The driver, Scott – a proper Geordie Lad – soon got into position ready to deploy the massive working platform. For such a huge machine, it was highly maneuverable and simple to operate and within a few minutes, we were positioned roughly ready to load up our tools and materials and descend to the deck to position more accurately. Getting onto the deck meant climbing onto the truck, over a small bridge and down inside narrow cage to the bottom, so the first time is a bit daunting, but once done everybody was at easy with it.
Once underneath, the problem was very obvious – years of fouling had built up on all ledges and completely buried the shafts and bearings of the bridge, corroding and filling the grease wells. The great thing about the Moog is that the platforms extends under the full length of the bridge – 10mt or so – allowing 5 of us to work to clean the ledges at a time.
The cleaning was laborious and time consuming, but every trace needs to be removed, cleaned and decontaminated to allow the engineers to work safely on the mechanisms. We removed in excess of 800Kg of guano off the structure to be disposed of safely.
Once cleaned, we could then start the process of proofing the structure. With a moving structure, we carefully planned the design to ensure the mesh to be fixed to the fixed side and the moving side without interference when the bridge was finally opened, but still not allow pigeons inside the chamber. As this was over brackish sea / fresh water of a tidal estuary, we chose stainless steel mesh and fixings to provide a long maintenance free life for this structure.
The project all went according to plan, and over the three days we worked closely with the TM guys and especially Scott, all were so helpful and professional it was a pleasure to deal with them – building strong relationships on site is vital to getting the work done safely and on time.
Not all our sites are in such beautiful surroundings as this so after work we all went for a long walks along the sea front, up onto the pier and had a few drinks just enjoying the weather – 3 days of brilliant sunshine – a rare treat for the team.
So if you have a bridge project or a bird proofing problem, call Rapid ESL on 01635 247192 or Contact Us Here for advice and ideas on how to deal with the problem.