tunnelling contracts were announced in February 2015: West: Joint venture of BAM Nuttall, Morgan Sindall and Balfour Beatty Group Central: Joint venture of Ferrovial Agroman UK and Laing O'Rourke Construction East: Joint venture of Costain, Vinci Construction Grands Projets and Bachy Soletanche In August 2015, the independent investors to finance and deliver the scheme were confirmed. Bazalgette Tunnel Limited, a new special-purpose company appointed to take the project forward, received its licence from Ofwat as a new regulated utilities business, separate from Thames Water. The special-purpose company is backed by pension funds and other long-term investors represented by Allianz, Amber Infrastructure Group, Dalmore Capital and DIF. The funding scheme used was later called the Regulated Asset Base (RAB) model, and be used in the nuclear industry. If the cost overruns by more than 30%, the government would have to provide additional equity finance. Planned timeline 2014: Planning decisions and approval 2015: Main works and financing contracts awarded 2016: Primary work completed; Main works preliminary construction begins 2018: Tunnelling begins 2019: Secondary lining begins 2022: Tunnelling ends 2024: All works completed (now scheduled for 2025). In August 2020, during the COVID-19 pandemic, a project lockdown and revised working practices meant the project was delayed by nine months and had incurred additional costs of £233m (taking the estimated project cost to £4.133bn). Completion was targeted for the first half of 2025. Controversy Since the initial proposal, questions focussed on the cost, the location of construction sites, duration, disruption, and whether a tunnel was the correct solution for London and for Thames Water customers. Cost and reward to the business owners The £4.3bn cost of the Thames Tideway Tunnel project is to be funded by Thames Water customers. This has angered customers who dispute an accounting practice confirmed by the industry regulator. Ofwat confirmed the extent of leveraging on the balance sheet, reducing tax due and allowing annual payouts of fairly typical levels of dividendsmoney some customers feel should have cut the cost of the scheme. Thames Water maintains it has done nothing unusual by making tax-deductible investments in the natural and proper domain of its business which reduces tax; this is conventional practice. It explains the money raised was used for essential maintenance and upgrade works. The earliest customers’ bills would be affected was 2014–15, with charges rising gradually after that. The project was estimated to add up to £70 to £80