A specialist tunnel boring machine is set to get to work in Shanklin next week when it begins tunneling 22 metres below the surface as part of a major £4million scheme to improve bathing water quality in the town.
Since last September, work has been taking place to replace and redirect sewers in the area of Arthur’s Hill with a view to improve the resilience and capacity of the sewerage network at times of heavy storms. The increased capacity is said to be essential in helping reduce the risk of releases to the sea and will also help protect homes from flooding.
The 12m long machine will be lowered into a specially built shaft at St Boniface Road next week. Then, on Thursday, the teeth of the 32-tonne ‘mole’ will cut a 1.8m wide tunnel through the rock in the direction of Wilton Park Road at a rate of 7.5m per day.
The tunnel has a life span of around 120 years and will be some 300m in length. However, residents shouldn’t know work is taking place as vibrations should be kept to an absolute minimum with no impact on the surrounding area.
Every aspect of this 3-year long project has been meticulously planned and the tunnel boring machine will be checked every 300mm for accuracy. Once the machine reaches Wilton Park Road it will be lifted out, transported back to St Boniface Road and then lowered down the shaft once again to begin tunneling towards Hope Road.
The new sewerage pipe will increase capacity by some 750,000 litres and will result in a 30-40% reduction in spills into the sea.
Local councillors and press were invited along to the site in Shanklin today (Thursday) where the project was presented in detail. There was an opportunity to see the St Boniface Road shaft before it is covered up for good and the operation of the tunnel borer was explained in detail.
Councillor Sara Sheath restored a tunneling tradition by naming the machine ‘Marthur’; it was called Arthur by mistake but superstitions say that each machine must have a woman’s name.
Work is expected to be completed in April before the road is fully reinstated during May – just in time for the summer bathing season.
For more information about Southern Water’s Bathing Water Enhancement Programme and the work in Shanklin, visit https://www.southernwater.co.uk/Media/Default/PDFs/BWEP-Shanklin.pdf.