New River Company is the earliest direct ancestor of Thames Water today. During the 1850s, Dr John Snow and William Farr's identification of the 1854 Broad Street cholera outbreak provided a stimulus to the better treatment of sewage. The Thames Conservancy was established in 1857 with unified control over water supply, drainage and navigation. The Great Stink occurred in 1858, and focused government and public opinion on cleaning up the Thames. Joseph Bazalgette's remediation of The Great Stink provided the company with much of London's present Victorian sewerage infrastructure and several listed buildings within its portfolio of sites. In 1904 The New River Company and eight other water companies serving London were taken into public ownership under control of the newly founded Metropolitan Water Board, and in 1973 these responsibilities were transferred to the Thames Water Authority. Privatisation and listing In 1989, the responsibility for navigation, regulatory, river and channels management inherited from the Thames Conservancy, was transferred to the National Rivers Authority which later became part of the Environment Agency. The remainder of Thames Water Authority was privatised as Thames Water Utilities Limited. The company was listed on the London Stock Exchange and became a constituent of the FTSE 100 Index. Following international expansion, Thames Water became the world's third largest water company in 1995. Takeovers Thames Water plc was acquired by the German utility company RWE in 2001. As well as its British operations, it continued as an international water treatment consultancy and acquired further overseas operations. On 17 October 2006, following several years of criticism about failed leakage targets in the UK, RWE announced it would sell Thames Water for £8 billion to Kemble Water Holdings Ltd, a consortium led by the Australian Macquarie Group. In December 2006, the sale of Thames Water's British operation went ahead, with RWE keeping the overseas operations. Under the new ownership, the company re-focused its efforts on improving its operational performance and in 2007 announced the largest-ever capital investment programme (£1 billion p.a.) of any UK water company. In 2012 some of the company's stock was acquired by the BT Pension Scheme (13%), the Abu Dhabi Investment Authority (9.9%) and the China Investment Corporation (8.7%). Thames Water was a Tier Three sponsor of the 2012 Summer Olympics in London. Recent years In 2017, under the government's Open Water programme, and in common with all water and sewerage companies, Thames Water must