More frequent dry seasons with low rainfall are increasing reliance on seawater desalination, which consumes more energy than other water treatment methods. Even during seasons of heavy rainfall, the amount of rainwater and stormwater that can be collected and treated into potable water is limited by the availability of containments within Singapore’s land area.

During wet periods, therefore, the plant’s dual-mode technology allows the option of switching to treating reservoir water, resulting in more effective water use, operational flexibility and optimized operational costs, because reservoir water treatment consumes only one-third of the energy required for seawater desalination.

 As a result, the Keppel Marina East Desalination Plant can produce up to 137,000 cubic meters — equivalent to 54 Olympic-size swimming pools — of drinking water per day, regardless of weather conditions, ensuring a resilient and stable supply.

Making infrastructure work harder for urban sustainability

Not only is the Keppel plant efficient, but it blends neatly into the local environment, thanks to its structure being mostly situated underground. Meanwhile a 20,000 square meter green roof — with rainwater harvesting for irrigation — provides space for bike and walking trails for community recreation. In fact, seen with a satellite view, the plant looks like a park, rather than a desalination plant. Around 80 percent of its footprint is accessible to the public.

 This dovetails with one of the key objectives in the C40 agenda to prioritize the building of “nature-based solutions,” to help reduce the risks of extreme heat, drought and flooding, and to improve livability as well as physical and mental health. Instead of a traditional industrial design that would become a barrier to community access, the Keppel Marina East Desalination Plant forms part of Singapore’s public park system and has become a place for people to gather to enjoy the green space and views. Ultimately, maintaining such green space in cities contributes to efforts to combat climate change by absorbing carbon and lowering urban temperatures.

The combination of resilience and sustainability — carried out in a cost-efficient manner — will increasingly be a key feature of how cities must approach climate adaptation as they seek to confront the effects of climate change on the most population-dense zones on the planet.

The art of partnership

A new framework for water resilience launched at World Water Week in August 2021 emphasized the importance of building partnerships between local and global, civil society and science and, crucially, public and private participants. Indeed, a public-private partnership was a vital aspect to the success of the Keppel Marina East project. The plant is a partnership between Keppel Infrastructure and Singapore’s national water agency PUB, with Keppel building and operating the facility under a Design Build Own Operate model and a 25-year water purchase agreement.

 Such arrangements involving developer and operator are a highly effective way of approaching urban sustainability projects, because more effort tends to be invested in analyzing lifecycle costs and using the most efficient equipment possible. To Keppel, the partnership has yielded a number of good practices that could be replicated elsewhere, from detailed consideration of the construction sequence and environmental issues to its high level of automation. The outcome is a plant uniquely located among the population it serves, working efficiently and sustainably in a tight urban setting.