Lok On Pai “desalting” plant, 1975-1981

HF: Desalination (or “Desalting” as it appeared to be called at that time)  was a source of water in Hong Kong between 1975 and 1981. A large desalination plant was commissioned at Lok On Pai, near Tuen Mun, in 1975, but was decommissioned  in 1981 because its operation was more expensive than importing water from Dongjiang in China.

A Water Supplies Dept report provides considerable detail and is linked below. It was obviously written before the plant’s closure.

In February 1971 an experimental distillation plant was built at Lok On Pai and ran for twenty months.

Lok On Pai - experimental distillation plant 1971

In May 1971 the HK Government officially announced that it intended to build a large scale “desalter” at Lok On Pai on a piece of land measuring about 9 hectares.

The consulting engineers were Binnie & Partners (HK).

IDJ has supplied this aerial photo of the plant. He adds, at the top left is the bay that is now covered by the “Gold Coast” development.

Lok On Pai De Salting Plant IDJ Image

IDJ further adds, When the desalting plant was being developed a number of CLP staff left the company and became government employees to manage and operate the de-salting plant. However the accelerating rises in the cost of fuel oil caused by issues in the Middle East meant that by the time it was built it was restricted in its operations. Also relations with China improved so that secure water supplies from across the border were less at risk. This was about the time President Nixon visited China and met Chairman Mao when all round relations improved between China and the West.
Please refer to Ernest Evans’ comment below.

Later when the Castle Peak Power Station project was being developed at nearby Tuen Mun I believe there was some discussions with CLP about taking over the operations of the de-salting plant or incorporating such a plant into the new power station’s construction as many of the operational principles and the engineering were similar to a power station. This proposal faded away. Probably due to differences between CLP’s commercial commitments and HK governments desire to off-load something that was by now something of a “White Elephant.” 

The complex was officially opened by the Governor of Hong Kong, Sir Murray MacLehose, on 15th October 1975

Lok On Pai - desalting plant map

The plant was decommissioned  in 1981.

“In the early 1970s the government decided to install a water desalter in Hong Kong. It spent billions of dollars installing the desalter, but the plant operated for only a few years. After the water supply from China was secured in 1982, the plant was left idle. The operating costs to maintain the desalter were found to be be enormous. It was not until 1991 that the plant was dismantled. With hindsight, one may query the decision to invest in and to maintain the desalter, which did not really do much to help Hong Kong’s water supply problem.” (1)

If the Lok On Pai desalting plant was demolished in 1991 I wonder why it took ten years for this to happen?

This article was first posted on 10th October 2014.


  1. Privatising Water and Sewage Services, Pun-Lee Lam and Yue-Cheong Chan, City University of Hong Kong Press, 1997


  1. Lok On Pai desalination plant Water Supplies Dept report.
  2. There is a book, Lok On Pai Desalting Plant, in English, WSD, pub PWD, 1978.
  3. Lok On Pai desalination plant [1975-1991] gwulo.com
  4. Hong Kong built a desalination plant to combat a water shortage – but water from China was cheaper SCMP 9th October 2020

Related Indhhk articles:

  1. Lok On Pai “desalting” plant, 1975-1981 – mystery of non-demolition of main building
  2. Lok On Pai “desalting” plant, aerial photos 1973, 1982 and 2013
  3. Lok On Pai ‘desalting’ plant – as Transshipment Centre used by the PAA 
  4. Lok On Pai ‘desalting’ plant – site visit photographs including a great surprise!
  5. Lok On Pai ‘desalting’ plant – 2014 HK Urbex visit and photographs
  6. Hong Kong Petrochemical Co Ltd – Lok On Pai Jetty, Tun Muen
  7. The Castle Peak ‘A’ and ‘B’ Power Station
  8. Binnie & Partners, engineering consultancy, Hong Kong reservoirs and more…
  9. Sir Alexander Binnie, Binnie & Partners



  • Thomas Ngan

    Hi there,

    The main building still exist today. Only the chimneys and the generators had been demolished/removed.

    The lot had been occupied as a weekend/holiday flea market for quite a few years. Don’t know what might have happened in the past year or so as I have not been there for almost a year.

    Last time I was there some movie makers had been filming some Police/Crime movie there with lots of people in tactical gears.

    Thanks & Best Regards,

  • Ernest Evans

    This account is basically correct. The political climate in China, changing under Deng’s influence was a major factor, guaranteeing a stable water supply to HK. In earlier years when we were concerned about supplies from China the plan was to combine nuclear power with desalination. So the Lok On Pai plant was to be a starter project to determine the feasibility of large scale production.

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