Harvesting rainwater from greenhouse rooftop for crop production

The rooftop rainwater harvesting means the collection of water through rooftop of the house or any other structure. This system consists of three basic components such as catchment area, conveyance system and storage facilities. The study was conducted at the Research farm, Department of Soil & Water Engineering, Punjab Agricultural University, Ludhiana to find the optimum size of the storage tank for harvested rainfall from the greenhouse rooftop. The rainfall data of Ludhiana district for 30 years was analyzed for the water harvesting potential. From 560 m² greenhouse rooftop rainwater harvesting potential is 235.84 m³, which can meet around 60% of the water requirement for raising sweet pepper crop by using drip irrigation. If the size of the polyhouse varies from 560 m² to 4000 m², the size of the collecting pipes and storage tank capacity varies from 20 cm to 25 cm and 125 m³ to 892 m³, respectively.