Thames Water have responded to claims its customers could see their bills could rise by as much as £80 a year to help pay for a £4.1bn super sewer in London.
A spokesman said: "We previously made it clear that bills need to rise to pay for the cost of the Thames Tideway Tunnel and are now able to give our customers advance warning of the likely increase and the timing.
"Ofwat sets limits on water bills in line with the work that water companies need to do, and will scrutinise the Thames Tideway Tunnel costs to ensure they are kept as low as possible."
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