Question to the Department for Environment, Food and Rural Affairs:

To ask Her Majesty’s Government what assessment they have made of whether the additional cost of £70 to £80 per annum, at 2011 prices and based on a 50 per cent probability of cost overruns, to all Thames Water customers of the Thames Tideway Tunnel, as quoted on page 83 of the prospectus of Thames Water Utilities Cayman Finance Ltd, represents good value for money for the consumer.

The impact of the Thames Tideway Tunnel on Thames Water customer bills is expected to be £20-£25 per year (at 2015 prices) by the mid-2020s. This is about a third of the initial estimate of £70-£80 per year in 2011, assessed at an early development stage of the project, and represents good value for money for customers. It follows the successful competition by Thames Water Utilities Ltd, completed in August 2015, to procure an Infrastructure Provider to finance and deliver the Thames Tideway Tunnel. The Thames Water Utilities Cayman Finance Ltd prospectus quoted by the Noble Lord is dated 26 June 2015 and so was prior to this procurement.