This chapter examines the transformation of Mahendragarh’s agricultural landscape from a drought-prone, monsoon-dependent region in 1917 to a diversified and water-secure agricultural economy by 2023. The development of canal infrastructure, with a net gain of 520.8 km over the century, facilitated crop diversification, stabilized agricultural output, and enhanced livelihood opportunities. The study highlights the role of sustained irrigation development in enabling the shift from drought-tolerant crops like bajra to more profitable crops such as wheat, vegetables, and fodder. Using historical data, thematic figures, drought severity analysis, and Normalized Difference Vegetation Index (NDVI)-based insights, this chapter analyzes the impact of irrigation on cropping patterns, vegetation health, and agricultural productivity. The findings reveal significant improvements in canal-fed areas, contrasted by persistent challenges in less-irrigated regions, offering critical lessons for sustainable agricultural development in semi-arid regions globally.