Nimbus-1 is a modular, three-piece rainwater harvesting system designed for domestic use, specifically personal hygiene, in households with intermittent water supply. It solves water scarcity issues by capturing and storing rainwater in a 560-liter main tank. The system is sustainable because it reduces reliance on municipal water, has a repairable design, and uses a 20-liter container as a consumption regulator to encourage conscious water use.