A member of the Eton public school O.T.C. (Officers Training Corps) practising shouting out orders during a training session, 20th January 1940. (Photo by Hulton Archive/Getty Images)

A model practices her walk ahead of Dakar fashion week on Goree Island in Dakar, Senegal, on December 03, 2022. The 20th anniversary of Dakar fashion week is held in a preserved colonial era fort on Goree island, which was one of Africas biggest slave trading centres during the 15th and 16th century. (Photo by John Wessels/AFP Photo)

Tom Kaulitz and Heidi Klum attend Heidi Klum's 20th Annual Halloween Party presented by Amazon Prime Video and SVEDKA Vodka at Cathédrale New York on October 31, 2019 in New York City. (Photo by Craig Barritt/Getty Images for SVEDKA)

A participant shows off a belt buckle during the 20th annual Seattle Invitationals, an amateur Elvis impersonator competition, in Seattle, Washington January 23, 2015. The event drew hundreds of spectators for 20 contestants at the Crocodile, a venue in Seattle's Belltown neighborhood. (Photo by David Ryder/Reuters)

A woman stands next to a giant jandal on Tamarama Beach as giant sculptures are installed ahead of the “Sculpture by the Sea” exhibition in Sydney on October 19, 2016. Celebrating it's 20th anniversary, Sculpture by the Sea is the world's largest annual, free-to-the-public, outdoor sculpture exhibition. (Photo by William West/AFP Photo)

To mark World Water Day, on March 22nd Solidarités International and its agency BDDP Unlimited will roll out a campaign to build awareness of the scourge of undrinkable water.