Osborne Awarded Gold and Silver Sites
Well done to the Osborne teams working on the River Axe Slymlake Scour Project and the Feltham Bridge and platform extension and the Ewell West Access for All (AfA) projects, as these sites have achieved the prestigious ‘Route to Gold’ status from Network Rail.
Route to Gold is a performance measurement initiative within the IP Southern supply chain.
The initiative aims to promote collaborative working behaviours, reduce costs caused by re-work and embed a culture of continuous improvement within the rail industry.
Network Rail scores their supply chain on the quality of products delivered, on projects and the behaviours associated with these.
River Axe Slymlake Scour is the top scoring site.
The project is technically demanding but is also located within two statutory nature conservation sites requiring extensive liaison with Natural England and the Environmental Agency
so that the river flow and fish migration will not be impeded while piling is in progress.
This is a three span under-bridge carrying two tracks over the River Axe and it has been assessed that there is a medium to high risk of the foundations scouring out in the future. The intervention agreed is to install concrete bags mattresses between the piers and reinstate the embankment with bag work revetments which will be completed with grout mattress type formwork and reinstated with sub-soil from the site.
The project involves the construction of steel pile caissons in two phases to divert the river course, allowing each of the three piers and their adjacent beds to be pumped out.
The site of works is located within two statutory nature conservation sites. The river has been so designated due to its diverse aquatic and marginal flora, the wide variety
of habitats for invertebrates and the presence of important species of fish including sea lamprey, brook lamprey and bullhead.
It is a valuable habitat for breeding birds and otters can also be found at the site.
The project ensured that there would be adequate fish passage in both phases of the work with fish rescue being carried out by a competent and qualified contractor.
Water pollution management work will also be undertaken in a de-watered area so as not to pollute the river while working. When the cofferdam is released after the work, it will be released in stages so that the river is not silted up.
The project is due to be completed on 5 October 2019.