River Thames to the strong current of the river, but also other river users. Organised swimming events take place at various points generally upstream of Hampton Court, including Windsor, Marlow and Henley. In 2011 comedian David Walliams swam the from Lechlade to Westminster Bridge and raised over £1 million for charity. In non-tidal stretches swimming was, and still is, a leisure and fitness activity among experienced swimmers where safe, deeper outer channels are used in times of low stream. A Thames meander is a long-distance journey over all or part of the Thames by running, swimming or using any of the above
River Thames compared with the late 19th and early- to mid-20th centuries and aquatic life has returned to its formerly 'dead' stretches. Alongside the entire river runs the Thames Path, a National Route for walkers and cyclists. In the early 1980s a pioneering flood control device, the Thames Barrier, was opened. It is closed to tides several times a year to prevent water damage to London's low-lying areas upstream (the 1928 Thames flood demonstrated the severity of this type of event). In the late 1990s, the long Jubilee River was built as a wide "naturalistic" flood relief channel from Taplow to Eton