The Politics Show London
The government, the Mayor's office and water companies are backing a plan for two gigantic new sewers
The Thames holds a dirty secret. Millions of tonnes of rainwater mixed with raw sewage is pumped into the river every year.
Because of an increase in population and loss of green spaces, for the last 15 years the problem has been getting worse.
Already in November we have seen 9.2 million tonnes of combined rainwater and sewage pumped into our rivers.
In terms of volume released, it is on course to be the worst month in years.
However, in summer when there is less water in the Thames and what we have is warmer, we are more likely to see fish die because of the pollution.
'The Great Stink'
London's sewers date from the 1860s. Before that the Thames had been virtually an open sewer.
After the so-called "Great Stink" of 1858 - when the smell became so bad that Parliament closed - the engineer Joseph Bazelgette designed a new system of sewers. That system is now under great strain.
The cost of the new sewer is currently believed to be £2.2bn
But a solution might be underway.
The government, the Mayor's office and water companies are backing a plan for two gigantic new sewers.
Called the Tideway tunnels, the sewers will be run under the Thames and River Lee.
If completed, they will be absolutely vast - larger than the Channel Tunnel.
But of course, these things do not come for free. The cost is currently believed to be £2.2bn - or according to one estimate an extra £43 every year on the average water bill.
So while Londoners may not like the idea of sewage being pumped into our waterways, are the Tideway tunnels, which will cost the average household hundreds of pounds each, something we really want to pay for?
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