Deserts and malaria disease are antonymous concepts. It is also astonishing to learn that human interventions can bring out such drastic change of landscape that the impossible appears in a distinct manner. This is the story of malaria in the Thar Desert which has become 'possible' due to the introduction of a sustained water supply in the Thar Desert of western India through the hundreds of kilometers long Indira Gandhi Canal system. The introduction of water in a desert ecosystem and its implications have been analysed here with respect to the geographical factors and the development of malaria disease in the Thar Desert districts.