Fishermen jump into a small river to catch trout as they celebrate Fischertag (Fisherman's Day) in downtown Memmingen, southern Germany, July 25, 2015. The annual Fisherman's Day (Fischertag) tradition goes back to the year of 1465 where every fisherman who were born in Memmingen tries to catch trout from the river. The participant who catches the biggest trout will be named the “Fisher King” for one year. (Photo by Michaela Rehle/Reuters)

In this November 30, 2017 photo, Douglas scoops up mud from the bottom of the polluted Guaire River, in search of gold and anything valuable he can sell, in Caracas, Venezuela. Some stretches of the river smell of sewer while others emit a toxic odor of fuel, a stench that stays in ones nose for hours after leaving the water. (Photo by Ariana Cubillos/AP Photo)

A Naga sadhu, or naked Hindu holy man, poses for a picture after taking a holy dip in the Godavari River during Kumbh Mela, or Pitcher Festival, at Trimbakeshwar in Nasik, India, Sunday, September 13, 2015. Hindus believe taking a dip in the waters of a holy river during the festival, will cleanse them of their sins. According to Hindu mythology, the Kumbh Mela celebrates the victory of gods over demons in a furious battle over a nectar that would give them immortality. (Photo by Rafiq Maqbool/AP Photo)

Washermen put their clothes out to dry on the banks of the River Yamuna as seen from a railway bridge near Agra, India, Saturday, December 17, 2022. (Photo by Rajesh Kumar Singh/AP Photo)

A train passes as floodwaters from the Tule River inundate the area after days of heavy rain in Corcoran, California, U.S., March 22, 2023. (Photo by David Swanson/Reuters)

People watch a brig with scarlet sails floating on the Neva River during the Scarlet Sails festivities marking school graduation in St. Petersburg, Russia, early Saturday, June 25, 2022. (Photo by Dmitri Lovetsky/AP Photo)

A laborer is transporting used oil durms by a hand-pulled vehicle near Buriganga River in Dhaka on June 12, 2021. (Photo by Md Rakibul Hasan/ZUMA Wire/Rex Features/Shutterstock)

A giant panda named Kai Kai looks on as he opens a gift to celebrate his upcoming 14th birthday at the River Safari wildlife park in Singapore on September 10, 2021. (Photo by Roslan Rahman/AFP Photo)