STP is an Independent Sewerage Treatment Plant for decentralised water residences. It features a modular detachable system when decentralised solution is required for treating sewage for settlements in remote places. The i-STP is 350 L and is easily transportable using boats to fix the technology below toilets in water villages in Borneo. The treated discharge meets SPAN’s (National Water Services Commission) Standard A. The i-STP is a design innovation by taking a typical anaerobic-aerobic treatment plant system into a detachable modular system. The chambers could be separated into two parts for easy transportation by boat and then wrapping the units around, the structural column below the house’s toilet.