100ft sewer crater 'will cost London customers £200 each'

Thames Water customers may have to pay £200 a head for the construction of a 100ft hole for a "super-sewer", it was claimed today.

The proposed crater would be needed to pump out at least one million tonnes of soil to construct a £2.5billion tunnel under the Thames which will effectively act as a giant sewage storage tank.

Constructing the 20-mile tunnel will take eight years.

The site of the crater is likely to be Ravenscourt Park or Furnivall Gardens in Hammersmith. There will also be five smaller connecting shafts in the area, each around 32 feet in diameter.

In a letter to Hammersmith and Fulham council, Thames Water said the borough would have to be the starting point for the tunnel, running east to Beckton.

Council leader Stephen Greenhalgh said: "We don't want sewage seeping into the Thames but surely building a £ 2.5billion septic tank under our river, obliterating open spaces, bringing chaos to the borough for eight years and landing residents with a £200-plus bill is not the answer."

Thames Water said in its letter that no decision on sites had been made and it was consulting with boroughs to discuss how it might mitigate potential impacts.

"This is a large civil engineering project that will obviously have an impact on London boroughs," it said. "For this reason we are consulting with them at a very early stage."

It added: "As the funding package for this project is still to be agreed with [regulator] Ofwat, it is premature to put any cost on consumers."