Southern Water has admitted that it doesn’t fully understand why a major sewer pipe collapsed in Ryde earlier this year, but says works are taking place to prevent a repeat situation in the area.
It was back in January that a 1-metre wide sewer pipe catastrophically failed at Appley some 10 metres underground. This has led to over 10 months of disruption beside the seaside with emergency pumping equipment drafted in to divert all of Ryde’s wastewater away from the collapsed section of pipe.
A photograph released by Southern Water has, for the first time, revealed the true extent of the situation faced by engineers, showing how the top of the pipe caved in and filled the crucial pipe with debris.
The failed sewer has now been fully repaired with both a steel sheath and a glass fibre insert put in place around the existing pipe. However, it has been identified that the 40-year-old pipe which runs from the repaired section into the low-level pumping station is potentially at risk of collapse too.
Southern Water has taken the decision to complete a further 200m of work to help prevent a similar situation from happening in the future. This includes a distance of 130m between shafts 1 and 2, which will result in some further disruption in the North Walk area from mid-November.
It has been confirmed the road will be temporarily widened and almost 20 car parking spaces will be suspended whilst contractors install more pumping equipment to enable the proactive, preventative efforts to encase the concrete pipe in steel. North Walk will remain open to traffic.
It is currently envisioned that gravity-led flow will be restored by Christmas, but it could be as late as the end of February until the area is returned to normal. Reinstatement works – which includes backfilling the newly-built shaft 2 – are expected to begin in the New Year.
When questioned by Island Echo as to why the collapse went undetected until the sinkhole appeared, no real answer could be given. It has been suggested that flow monitors at the nearby pumping station may not have detected a change if sewage was still able to pass through the pipe, but it’s hard to believe the rate went unchanged from the dramatic photograph above.
There have been assurances from Southern Water that investments are being made in digital technologies to help identify blockages in pipes in the future, although no inspection of the sewer pipe has been carried out to date beyond shaft 1 at the junction of North Walk and Canoe Lake Road.
At least they have admitted they don’t know why it collapsed rather than blame someone else. And 40 years is a long time so its not done too bad. Its most likely a bad bit of concrete on the pipe from when it was built.
Is 40 years a long time for a sewer pipe to last? I honestly don’t know the answer but I dread to think that every sewer pipe in the country will need digging up and replacing every 40 years. Surely they are expected to last longer than that? I have in the back of my mind that the sewers in London were built in the 1800s. But, either way, 10 months seems like an extraordinary length of time to replace a pipe. For a similar length of pipe in, say, central London, would they honestly get away with taking 10 months to replace it? I don’t think so.
Let’s hope the weather when bitterly cold doesn’t freeze the overground temporary pipework and cause massive blockages for Ryde.
Lucky they haven’t built thousands more homes yet, or the pipework would need to be even larger to cope.
Hope they take those pallets out and what clown flushed blue plastic sheets, Greta will swoon if she sees such in case a Cod swallows the lot.
I can see exactly why it collapdsed, when they backfilled the trench in which they initially laid the sewer, thy put large rocks on top of the pipe and over the years as the disturbed groung compacted these rocks put pressure points on the pipe and eventually crushed it. You can see one of the rocks poking into the pipe in the photo.
Or after it was put in the group properly the council came along later and messed it up with unnecessary projects like the one at the bus station.