According to the project manager of the road Chen Xingda, when the motorway was first proposed in 2013, there were three different possible routes. Two of the routes involved digging a tunnel through the mountains in the area. The third was a longer route and involved building on water. Engineers on the project chose the third option because that would enable them to protect the abundance of plants and woodland in the mountains. Those involved in the project claim this to be China’s first “ecological overwater road”. The overwater highway cost about 2 million yuan (US$320,000) to construct which was nearly half of the 4.4 million yuan ($700,000) it cost to build the entire thing.
Source
