Boat crew members train on the waters of the Tonle Sap River on the morning of the first day of the Water Festival on November 13, 2016 in Phnom Penh, Cambodia. The yearly three-day Water Festival is one of the most important holidays in Cambodia and celebrates the end of the rainy season and the start of the rice harvesting. The Festival also coincides with the Tonle Sap river reversing course, which it does twice a year. Approximately 2 million people are expected to attend this year's festival, during which 259 boats and nearly 20,000 oarsmen will participate in the races. After a fatal stampede resulting in the death of some 353 people during the Water Festival in 2010, it has been cancelled four times over the past five years, with weather used as an official excuse. (Photo by Omar Havana/Getty Images)

A man pushes a tub carrying children as he gets them back home after school at a flooded area in Duchang, Jiangxi Province, China, June 27, 2016. (Photo by Reuters/Stringer)

An Afghan girl carries water on her back as she climbs a hill in Kabul, Afghanistan February 20, 2017. A growing population is straining water supplies in Afghanistan's capital, forcing those who can afford it to dig unregulated wells ever deeper to tap a falling water table. Finding water in arid Afghanistan is virtually always a challenge, but a drop in the groundwater level in Kabul caused by overuse and drought is making it even more difficult for residents, especially the poor. (Photo by Omar Sobhani/Reuters)

“The 8th annual Water War on Friday in the center of Tel-Aviv, Israel turned into a battlefield, quite literally. As two thousand people were having fun in the square, some water-fighters took to more radical behavior, targeting passing cars, motorcycles and public buses”. – iReport.cnn.com (Photo by Sergey Demyanchuk)

A man wearing a Guy Fawkes mask enjoys a ride on a 350-meter (1148 feet) long water slide during 2015 City Silde Festa in central Seoul, South Korea, July 19, 2015. A 350 meter-long waterslide has been installed in downtown of Seoul, the longest waterslide to be recorded in Korea, according to local media. (Photo by Kim Hong-Ji/Reuters)

Labourers stack dried bricks inside a kiln, where they will be fired, at a brick factory on the outskirt of Sanaa, Yemen, June 1, 2016. Traditional mud brick tower houses have always been a source of pride to Yemenis, and over a year into a devastating civil war, they are also providing some much-needed jobs in the ancient capital Sanaa. (Photo by Mohamed al-Sayaghi/Reuters)

The Verzasca is a Swiss 30-km long mountain river originating at Pizzo Barone and flowing into Lake Maggiore. It is known for its clear turquoise water and vibrant colored rocks, as well as its treacherous currents. The Verzasca Dam is a few kilometers upriver from this lake.

Ethnic Cham Muslim people pass the time near their boats on banks of Mekong river in Phnom Penh July 29, 2013. About 100 ethnic Cham families, made up of nomads and fishermen without houses or land who arrived at the Cambodian capital in search of better lives, live on their small boats on a peninsula where the Mekong and Tonle Sap rivers meet, just opposite the city's centre. The community has been forced to move several times from their locations in Phnom Penh as the land becomes more valuable. They fear that their current home, just behind a new luxurious hotel under construction at the Chroy Changva district is only temporary and that they would have to move again soon. (Photo by Damir Sagolj/Reuters)