The maximum capacity of Wushantou's sluice gates is 1,500 cubic meters of water per second. At maximum flow, a rainbow is created. The spectacular views from the nearby suspension bridge have earned it the name "Rainbow Bridge."
烏山頭的溢洪道，最大溢洪量為每秒一千五百立方公尺，洩洪時形成的彩虹，因跨越溢洪道吊橋之上，形成特殊景象，而有跨虹吊橋之名。