New Hong Kong desalination plant begins delivering fresh water to 137,000 homes

The new Tseung Kwan O desalination plant is said to be the first to use reverse osmosis (RO) technology in Hong Kong. Construction of the first stage plant began in December 2019, and 4 years later, it began supplying fresh water to homes throughout the territories.

Commissioning ceremony for Tseung Kwan O desalination plant

The Water Supplies Department (WSD) of the Hong Kong Special Administrative Region (HKSAR) government engaged Binnies — an RSK group company to deliver a feasibility study for the project in December 2012. Subsequently, the Binnies Hong Kong team provided investigation, design and construction supervision for the first stage of the project up to its commissioning on 22 Dec 2023.

RO technology at Tseung Kwan O desalination plant

“It is now delivering drinking water to 137,000 homes across Hong Kong and represents a step towards a climate-proof and sustainable water supply,” Binnies Hong Kong managing director Andy Kwok said. “As the region faces increasing demand as the population grows, we are seeing more erratic rain patterns and severe drought exacerbated by climate change. With the plant in action, we have a more stable and safe fresh water resource.”

This first of the two-staged plant will provide fresh water to a population of around 370,000 and has a production capacity of 135 million litres per day, representing about 5% of Hong Kong’s daily demand, according to Kwok. He added that the commissioning of the plant meant that the team has achieved its goal of supporting the WSD in diversifying its drinking water supplies with a new ‘tap’ that is climate-resilient.

RO units at Tseung Kwan O desalination plant

The Tseung Kwan O project is a key initiative in the government’s water management strategy and route map to achieve water sustainability and security while supporting development in Hong Kong. Adopting seawater desalination supports these objectives and provides a supply of potable water that is not susceptible to the effects of climate change.

“When running at 100% capacity, the plant will take around 2hrs to desalinate water from the point of intake to product. The plant can draw around 340 million litres of seawater per day to produce 135 million litres of fresh water,” Kwok said. “The Binnies team was able to draw on expertise from colleagues across the business in the UK and Singapore to support the delivery of the works.”

Desalination is reportedly an energy-intensive process, and attention has been given to introducing measures to reduce raw resource use and to prevent waste. During the plant’s operation, solar panels will be used to provide renewable energy, resulting in a 16.2% reduction in grid-supplied energy for building services. Water recycling and reuse processes will also reduce freshwater consumption by 36.6%, and installed water saving devices will reduce freshwater use by 53%. Rainwater harvesting systems have also been installed to reduce water consumed for irrigation purposes by 67%.

The WSD has started the preliminary design for the second stage of the plant, and the adjacent site is also earmarked for future expansion, with a water production capacity that will meet around 10% of the overall fresh water demand in Hong Kong.

Images: Binnies