Water resources, as one of the most critical inputs in agricultural production, have faced increasing constraints in recent years due to climate change and unsustainable exploitation. This situation underscores the need to optimize cropping patterns and enhance water productivity. The objective of this study is to examine the effects of changes in irrigation methods and water-reduction scenarios on crop yield and net profit within the cropping pattern of the Hamadan–Bahar Plain, with particular emphasis on saffron, a strategic crop for strengthening agricultural resilience. During the 2023–2024 agricultural year, crop yield simulations were conducted under three irrigation methods (surface, sprinkler, and drip irrigation) combined with deficit irrigation scenarios of 5%, 8%, and 10%. The simulated yield results were subsequently incorporated as inputs into a Positive Mathematical Programming (PMP) model to assess the impacts of yield changes on total agricultural net profit. The findings indicate that crop yields varied significantly across the three irrigation methods, and under the 10% deficit irrigation scenario, most crops experienced noticeable yield reductions. Consequently, saffron was introduced into the cropping pattern due to its low water requirement and high economic potential. A comparative assessment of irrigation methods revealed that drip irrigation consistently outperformed surface and sprinkler systems across all scenarios, effectively compensating for yield losses and mitigating reductions in farm income. Economic results further demonstrated that expanding saffron cultivation, alongside the adoption of modern irrigation technologies, not only offset the profit losses associated with water scarcity but, in some scenarios, increased net agricultural income relative to the baseline condition. Therefore, integrating saffron cultivation development with drip irrigation systems can be recommended as a sustainable and economically viable strategy for water resource management and for enhancing the resilience of agriculture in the Hamadan–Bahar Plain.