the Tuaspring Desalination Plant. In June 2018, a third desalination plant, the Tuas Desalination Plant (TDP), was opened. Functioning also as a test bed for energy saving technology, the plant can produce of water per day. Together, desalinated water from SingSpring, Tuaspring and the Tuas Desalination Plants can meet up to 30% of Singapore's current water needs as of 2019. In 2019, government has identified five other coastal sites for future plants in the coming decades, with the objective of bringing the installed capacity to one million m³ per day, so that desalination will be able to meet up to 30% of Singapore's future water demand by 2060. In June 2020, Singapore began operating its fourth desalination plant, the Keppel Marina East Desalination Plant (KMEDP). In April 2022, a fifth desalination plant began operations, the Jurong Island Desalination Plant (JIDP). Water research and technology Sanitation Until 2010, wastewater in Singapore was collected through a sewer system that included 139 pumping stations that pumped water to six wastewater treatment plants. These pumping stations and plants were gradually decommissioned while a newer system, the Deep Tunnel Sewerage System (DTSS) was made operational. The Changi Water Reclamation Plant, the heart of the first phase of the DTSS, was opened by Prime Minister Lee Hsien Loong in June 2009. The first phase of the DTSS consists of a 48-km long deep tunnel sewer that runs 20 to 55 metres below ground, and channels used water to the Changi Water Reclamation Plant at the Eastern end of the island. The plant had an initial capacity of per day. Most of the treated used water is discharged into the sea through an outfall, while some of it is further purified into NEWater. The deep tunnel works entirely by gravity, eliminating the need for pumping stations, and thus the risks of used water overflows. At one-third the size of conventional plants, the Changi Water Reclamation Plant is designed to be compact. Centralisation of used water treatment at Changi also allows for economies of scale. In a second phase of the DTSS, the deep tunnel system is to be expanded to the entire island, with a second wastewater treatment plant at Tuas at the Western end of the island. Stormwater management The stormwater drainage system in Singapore is completely separated from the sewer system. It consists of 7,000 km of public roadside drains and about 1,000 km of