The start of digging work on the Lee Tunnel in London took a step closer last week, as the giant drill that will dig the four mile long tunnel was lowered into position into a gigantic shaft. The drill, ‘Busy Lizzie’ as was aptly named by local schoolboy Ryan Waters, who won a competition organised by Thames Water.

The drill has been lowered into the shaft in separate parts and will be rebuilt underground before tunnelling begins. When complete the Lee Tunnel will stop 16 million tonnes of sewage entering the River Lee every year when too much rainwater puts excessive pressure on the Victorian sewer system.

The drill is eight metres in diameter and 120 meters long and should take just under two years to complete the mammoth task.

The drill was transported to the shaft site at Beckton Sewage works on 60 lorries and was lowered into the shaft by a special heavy duty crane.

The chief executive at Thames Water, Martin Baggs, stated:

“This is a major milestone on our way to creating a cleaner, healthier River Thames and River Lee, by dealing with the unacceptable problem of sewer discharges into the river during heavy rainfall.

“The Lee Tunnel is the first of two tunnels, which will collectively capture an average of 39 million tonnes a year of sewage from London’s 35 most polluting combined sewer overflows.

“The Lee Tunnel will tackle discharges from the largest overflow at Abbey Mills in Stratford, which accounts for 40 per cent of the total discharge. That’s why we’re dealing with this, the worst one, first.”

Just days after Thames Water released a comic Christmas jingle featuring their staff dressed in Christmas clothing singing ‘bin it – don’t block it’, to the popular Christmas Carol ‘Deck the Halls with Bows of Holly’, the Thames Water sewer men were reeling, after more than one hundred baby fish were killed when turkey fat was washed down a sewer.

The incident in question happened when wrongly disposed of turkey fat blocked a sewer and polluted a pond. It happened at Britten’s Pond near Jacobs Well in Guildford, Surrey.

Thames Water were called to the incident last Tuesday and managed to clear the offending blockage quite quickly, however the oxygen levels in the pond dropped significantly which killed most of the fish in the pond.
The waste water company’s lab and sampling manager, Mark Handcock, stated:

“Any incident which kills wildlife is always very sad and this is a vivid example of the consequences of sewer abuse – putting anything other than human waste, water and loo roll down drains.

“We always see a dramatic increase in the number of blockages after Christmas because everyone is cooking roast turkeys and pouring the leftover fat down the drain which spills into our cold sewers and forms hideous fatbergs. These block the network and cause sewage to back up into people’s homes and gardens or into rivers and ponds.”

Thames Water have estimated that they will have to attend over 70,000 sewer blockages in 2012, with around 10% of these being internal sewer blockages, which can be prevented if people ‘bin it instead of block it’.

Thames Water employees have got into the festive spirit by posting a Christmas Carol on YouTube, asking people to stop the disposal of fat into the sewage network.

The employees, all dressed up in festive costumes, are seen singing the reworded song to the tune of Deck the Halls with Bows of Holly.

The sketch was filmed in a Victorian brick sewer in the heart of London and is aimed at highlighting the problems the water company face by residents disposing of liquid fat down the sink.

The singing sewermen lead chorister, Rob Smith, who also happens to be Thames Water’s chief sewer flusher stated:

“Anything other than human waste and loo roll has no business in our sewers. And fat is the biggest no-no of all. Christmas time is the worst time of year for fat blocking our sewers because of all the turkey grease that gets washed away. It goes down sinks easily enough when it’s warm but when it hits our sewers it cools down and sets hard forming hideous fatbergs. Last year we were called out 101 times on Christmas Day alone to sort out blockages.

“The sewermens’ war cry is: ‘Bin it – don’t block it.’ We are hell-bent on stopping hideous ‘fat bergs,’ which block sewers and can cause it to back-up into people’s homes and gardens, which is utterly hideous. We’re committed to preventing sewer blockages but we need people’s help. Listen to our song: ‘You must bin it – please don’t block it.’ Got it?”

Drain blockages in London are an all too common occurrence, as the city’s Victorian sewer system struggles with the pressure put on it by modern life.

When the Victorians built the London sewer network, they were not to envisage the population boom the city has seen over recent decades. And although the system has done well coping so far, there is still far too much sewage dumped into the River Thames at times of heavy rainfall.

Currently only around 2mm of rainfall can trigger a discharge into the River Thames from one of the 57 sewer overflows on the river. When the Thames Tunnel is built it will take the discharge from the 34 most polluting sewer overflows and transfer it to Beckton Sewage Treatment Works where it will be processed.

Thames Water say that on average a discharge is released around 50 times every year and a total of 39 million tonnes of sewage is released into the river. If the proposed tunnel build does not go ahead the forecast for annual sewage release is expected to increase to around 70 million tonnes, which could have a huge impact on the river and its wildlife.

Thames Tunnel project manager Malcolm Orford is giving a talk on the 13th of December about the current round of tunnel proposals put forward by Thames Water.

The free talk, which will be held at The Pier House in Chiswick at 7:30pm, will give people a chance to hear the latest information about the sewer project.

Currently over 39 million tonnes of sewage flow into the River Thames every year at times of heavy rainfall, as the city’s Victorian sewer system struggles to cope during times of heavy rainfall.

The plan is to capture overflow sewage from the 34 most polluting sewage outlets into the Thames and transfer it via the new ‘super sewer’ to Beckton Sewage Works where the waste will be treated.

The talk has been organised by Chiswick Pier Trust (CPT) who are a charity whose objective is to protect the River Thames and waterside areas. There will be time for questions factored into schedule and doors will open at 7:00pm.