The Changi water plant now is the largest water plant in Singapore, 800,000 m3/day sewage treatment capacity, 228,000 m3/day (60MGD) regeneration water capacity, the 1st phase project was finished and started operation in 2010, and the 2nd phase project started construction in 2015. The project chose PASS stainless steel piping coupling because of its easy maintenance. As the piping connector, the PASS coupling can be connected to the pipes quickly. The contractor chose PASS coupling to shorten the construction time, reduce the equipment’s occupied area and lower the project construction cost.