Johor Port (Malaysia), Rainwater Harvesting to Replace Freshwater for Cleaning and Irrigation
Johor Port in southern Malaysia is described by UNCTAD as the world's largest palm oil terminal. The port used about 2 million litres of freshwater a year for landscape irrigation and for cleaning warehouses, roads and office buildings (UNCTAD, 2022). The port's property manager developed a rainwater harvesting proposal during UNCTAD's TrainForTrade port management programme, with the aim of reducing the port's freshwater consumption (UNCTAD, 2022).
Approach
Match the water source to the use. The project targeted uses that do not need treated drinking water: irrigation and cleaning of warehouses, roads and office buildings (UNCTAD, 2022).
Choose suitable collection sites. The project identified three suitable sites within the port for rainwater collection (UNCTAD, 2022).
Put surplus water to work. Harvested water beyond irrigation and cleaning needs is used for plumbing and fire hydrants (UNCTAD, 2022).
Results
The system was installed between 2019 and 2020 at a cost of $86,000. It can harvest up to 10 million litres of rainwater a year, enough to fill four Olympic-size swimming pools, and paid for itself in two years (UNCTAD, 2022). UNCTAD also notes that the system helps reduce flooding risk and conserves freshwater for local communities during dry periods (UNCTAD, 2022). The source does not report measured freshwater savings after installation, or how much of the harvested volume is actually used each year.
Transferability
Many DMC ports in tropical climates have high rainfall and large roof and paved areas, and they use treated mains water for tasks that do not need it.
Rainwater harvesting for irrigation, washdown and fire water is a low-tech, low-cost first step, and Johor Port recovered its investment in two years.
Ports can start by measuring how much water these uses consume, then size storage to match, as Johor Port did when it selected suitable collection sites.
Sources
All information used for this case study was based on publicly available resources.