Through research and technology, Singapore has now found an integrated, effective and cost efficient way to solve the water challenges. Now, the nation has built a robust, diversified and sustainable water supply from 4 different sources known as the Four Nation Taps( water from local catchment areas, imported water, reclaimed water known as NEWater and desalinated water).

By increasing the efficiency of the four taps, Singapore has ensured a stable, sustainable water supply capable of catering the country's continued growth. 

The different ways Singapore has introduced to heal with water scarcity are:

1) Local Catchment Water:

   Due to the small island that doesn't have natural aquifers and lakes and with little land to collect rainwater, Singapore needs to maximise whatever it can harvest. 

   Currently, Singapore uses two system to collect rainwater and used water. Rainwater is collected through a comprehensive network of drains, canal, rivers and storm water collection ponds before it is channelled to Singapore's reservoirs for storage.
   With all the major estuaries already dammed to create reservoirs, PUB aims to harness water from the remaining streams and rivulets near the shoreline using technology that can treat water of varying salinity.

Reservoirs include:
-Pandan Reservoir
-Jurong reservoir
-Upper Peirce Reservoir
-Bedok Reservoir
-Lower Seletar Reservoir
-Murai Resevoir
-Sarimbun Reservoir
-Marina Reservoir
-Punggol Reservoir
-Kranji Reservoir
-MacRitchie Resevoir
-Lower Peirce Reservoir
-Poyan Reservoir
-Tenget Reservoir
-Pulau Tekong Reservoir
-Serangoon Reservoir
-Punggol Reservoir

Rivers Include:
Jurong River
Pandan River
-Ullu Pandan River
-Peng Siang River
-Tengah River
-Kangkar River
-Singapore River
-Kallang River
-Rochor River
-Geylang River
-Bedok River
-Changi River
-Selatang River
-Loyang River
-Tampines River
-Api Api River
-Serangoon River
-Pinang River
-Tong Kang River
-Punggol River
-Seletar Tiver
-Seletar Simpang River
-Khatib Bongsu River
-Sembawang River
-China River
-Mandai River
-Mandai Kechi River

2) Imported Water:

    Singapore has been importing water from Johor, Malaysia under two bilateral agreements.Under the agreements signed, the price of water is set at a very low level of less than 1% per 1000 imperial gallons. As of 2009, imported water has been reduced to 40% of total consumption. The two countries are in disagreements about the future price of water. In the absence of resolution, the Government of Singapore decided to increase self-sufficiency in its water supply.

3)New Water:

Use each drop of water more than once

   NEWater is high grade reclaimed water. It is produced from treated used water, more specifically waste water(sewage) that is further purified using advanced membrane technologies and ultra-violet disinfection , making it ultra clean and safe to drink.

   Developed by PUB after 3 decades, NEWater has passed more than 65000 scientific tests and surpasses World Health Organisation Requirements, testimony of its high quality and reliability.

NEWater is proof that using today's water treatment technologies, water of any quality can be treated into drinking water. 

   As of 2008, there are 5 NEWater factories, located at Bedok, Kranji and Seletar, Ulu Pandan and Changi water reclamation plants, producing 50million imperial gallons per day. NEWater is currently able to meet 30% of Singapore's water needs. By 2060, we plan to triple the current NEWater capacity so that NEWater capacity can meet 50% of our future water demand. 

   Another technology-based water source is desalinated water. In September 2005, Singapore turned on its 4th national tap, with the opening of the SingSpring Desalination Plant in Tuas. This plant can produce 30million gallons of water per day and is one of the region's largest seawater reverse-osmosis plant. 

   At the SingSpring plant, sea-water goes through a pre-treatment process where suspended particles are removed. In the second stage, the water undergoes reverse osmosis. This is the same technology used in the production of NEWater. The water produced is very pure and re-mineralised in the third stage.  After treatment, desalinated water is blended with treated water before it is supplied to homes and industries in the western part of Singapore.