Johor explores public supply from DayOne's expanded Kempas water treatment plant
Johor is studying whether surplus treated water from DayOne's Kempas Tech Park plant, which is expanding to 20 million litres per day, can be further treated for public use. Menteri Besar Datuk Onn Hafiz Ghazi has called for immediate technical discussions involving DayOne, Permodalan Darul Ta'zim a
JOHOR is exploring whether surplus treated water from DayOne's plant at Kempas Tech Park could undergo further treatment for public use, as the data centre operator expands the facility. The expansion will raise treatment capacity to 20 million litres per day (MLD), with the second phase expected to begin operating in the third quarter of 2027, state government news portal Media Digital Johor reported.
Menteri Besar Datuk Onn Hafiz Ghazi has called for an immediate technical discussion involving DayOne, Permodalan Darul Ta'zim Sdn Bhd (PDT) and Ranhill SAJ to assess the public-supply proposal, according to Bernama. Speaking at an event for the plant's second-phase expansion on Thursday (Nov 5), he said DayOne treats polluted water drawn from Sungai Tebrau for its operations, reducing reliance on treated water supplies intended for the public, The Star reported.
The newspaper quoted him as saying that surplus water could potentially be supplied to the public after an additional treatment process. He also welcomed the company's closed-loop cooling system, which recirculates water within its operations to improve efficiency. Media Digital Johor said the plant's first phase has been operating since March 2026, with capacity exceeding the campus's current requirements, enabling it to meet its data centre cooling needs without relying on drinking water from the municipal supply network.
The plant uses locally developed ultrafiltration membrane technology to treat river water on site. The initiative involves cooperation and coordination with Ranhill SAJ, PDT and Johor Special Water, according to the portal. Any community use of surplus treated industrial water would remain subject to suitable treatment processes, standards and technical requirements, it added.
Onn Hafiz said Sungai Tebrau has a flow of about 80 MLD, while DayOne's maximum consumption is around 10 MLD, Bernama reported. Those figures describe river flow and company consumption respectively, rather than the volume of surplus treated water available for public supply. The reports did not specify a confirmed public-supply volume, service area or commencement date.
DayOne's river-water treatment approach comes alongside other alternative-water arrangements for Johor's data centre industry. In a media statement dated Aug 11, 2025, Indah Water Konsortium (IWK) said its collaboration with Johor Special Water involved supplying 12 MLD of treated sewage effluent to water reclamation plants serving Bridge Data Centres and Computility Technology. The statement also outlined a separate arrangement for Johor Special Water to supply an alternative water source directly to DayOne.
Onn Hafiz said DayOne had realised about RM25 billion in investments in the state as at September, with the amount expected to reach RM28 billion by year-end, Bernama reported. He added that Johor would continue assessing data centre and artificial intelligence investments through a technical committee to safeguard the interests of the state and its residents.
