Elite athletes swim in the River Thames to raise awareness for clean bathing waters

Eight world-class and Olympic swimmers, representing all four UK nations, have been making their way along the River Thames this week, seeking to cover 124 miles in a relay-style swim. The swim is meant to raise awareness about the UK's dirty bathing waters, which advocates say is a major issue. If the waters were cleaned up, they could be used for recreational swimming, which could boost moods, activity levels and even bring in tourism money. The World's Bianca Hillier reports on the journey.