The supply of water to the public in Kuala Lumpur and its surrounding areas started in 1896 and was handled by the Public Work Department (PWD), which is currently known as Jabatan Kerja Raya (JKR). The water supply scheme was built in stages starting with the Ampang Impounding until the construction of Klang Gates Dam.

Jabatan Bekalan Air Selangor (JBAS) has been seperated from Jabatan Kerja Raya in 1972 and on 15 March 2002, Perbadanan Urus Air Selangor Berhad was incorporated. Later, on 1 January 2005, this organization was privatized and is now known as Syarikat Bekalan Air Selangor Sdn. Bhd.

Ampang Impounding

The first public water supply scheme that has been developed was the Ampang Impounding which is situated at Jalan Kolam Air Ampang, Taman Tun Abd. Razak, Ampang (District of Gombak), Selangor. Officiated by Al-Marhum DYMM Sultan Alaeddin Sulaiman Shah Ibni Al-Marhum Sultan Abdul Samad, it has the ability to produce 1.5 million litre per day (mld) of water. This scheme has managed to supply untreated water to government buildings as well as public places in Kuala Lumpur. The Bukit Maxwell reservoir has also been built under this scheme.

Ampang Impounding

Ampang Intake

In 1906, the second source i.e. the Ampang Intake which is located at Bukit Belacan, Ampang (District of Gombak) was built with the ability of 15 mld and had been increased to 18 mld. The slow sand filteration system was introduced and followed by the germs infection control by using a type of chemical i.e. the chloride of lime. The water was then supplied to people in Kuala Lumpur. Under this scheme, the Bukit Nenas reservoir, formerly known as Bukit Weld reservoir was built.

Ampang Intake	Slow Sand Filter

Klang Gates Dam

With the ability to produce 28 mld, situated in Hulu Kelang (District of Gombak), the Kuala Sleh Headworks scheme was built in 1928 and is currently known as the Klang Gates dam. The same treatment was applied as the Ampang Intake. The Sentul reservoir was built under this scheme. The source of water supply had semi-treated water process, (the water was distributed to villages in the Kuala Lumpur areas from 1948 to 1960) are :

- Gombak Setia or Mount Estate water supply
- Batu Cantonment water supply
- Sungai Tua water supply
- Sungai Besi water supply
- Sungai Way water supply
- Kampung Damansara water supply

Klang Gates Dam

After our Country achieved its' independence, the water supply especially in the Klang Valley had expanded remarkably due to economic growth. With the separation of the city's administration under the Federal Government in 1972, Jabatan Bekalan Air Selangor (JBAS) was separated from Jabatan Kerja Raya (JKR). Since that year, JBAS had created its own identity, objectives, and management system in all districts of the State of Selangor Darul Ehsan. Under the management of JBAS, the Sungai Langat Water Supply Scheme (including the building of Sungai Langat Dam) was completed to satisfy water supply demand up to early 1980.

In 1984, the Sungai Semenyih Water Supply (including Semenyih Dam) was completed to provide an additional 545 mld (120 mgd) clean water to areas in North West of Kuala Lumpur, Petaling Jaya, Shah Alam, and Klang. About RM 402 million was spent on this scheme.

To meet long-term requirement of water supply, JBAS launched a major water supply project called the Sungai Selangor Water Supply Scheme, which was implemented in three (3) phases. Included in Phase 1 was the construction of Sungai Tinggi Dam (formerly known as Sungai Buloh Dam).

The implementation of Phase 2 started in April 1996 and Stage 1 of the project, which has a capacity to produce 475 mld, was completed and began its operation in early November 1998. Stage 2 with an additional 475 mld was also completed in December 2000.

The Selangor State Governement also implemented Phase 3 of the Sungai Selangor Water Supply Scheme, which has a capacity to produce 1050 mld estimated to satisfy water supply demand for Selangor and Federal Territory of Kuala Lumpur until 2007. The project was implemented in stages beginning January 2000 until July 2005. The implementation of this scheme was done via Build, Operate, and Transfer (BOT) through a 30-year concession between the State Government and the owners of Syarikat Pengeluar Air Selangor Berhad (SPLASH).