The Banpo Bridge is a major bridge in downtown Seoul over the Han River, South Korea, connecting the Seocho and Yongsan districts. The bridge is on top of Jamsu Bridge, forming the upper half of a double-deck bridge; it is the first double deck bridge built in South Korea.

During periods of high rainfall, the Jamsu Bridge is designed to submerge as the water level of the river rises, as the lower deck lies close to the waterline. The bridge was built as a girder bridge and was completed in 1982.

The Moonlight Rainbow Fountain is the world's longest bridge fountain that set a record with nearly 10,000 LED nozzles that run along both sides that is 1,140m long, shooting out 190 tons of water per minute.

Installed in September 2009 on the Banpo Bridge, former mayor of Seoul Oh Se-hoon declared that the bridge will further beautify the city and showcase Seoul's eco-friendliness, as the water is pumped directly from the river itself and continuously recycled. 

The bridge has 38 water pumps and 380 nozzles on either side, which draw 190 tons of water per minute from the river 20 meters below the deck, and shoots as far as 43 meters horizontally. 

According to en.wikipedia