Water scarcity, driven by population growth, overuse, pollution, and climate change, threatens agriculture in Egypt due to
limited Nile water allocations. This study examines the effects of water shortages on crop productivity, soil salinity, and unofficial
water reuse in Eastern Nile Delta governorates using the SIWARE model under 0%–50% water reduction scenarios. Data sources
include agriculture, irrigation, meteorology, drainage reuse, and groundwater from relevant ministries and institutes. The model was
calibrated based on data from the year 2020. The results reveal that the crop productivity remained stable under moderate water
reductions (10%–15%) but declined sharply under a 50% reduction. On average, 85% of cultivated areas in North Sinai, Port Said,
and Damietta were classified within the critical range of average relative evapotranspiration (25%–50%), while Sharkia and
Qalyubiyya had 30% of their cultivated areas falling within this specified range. However, none of the governorates reached the
lowest productivity threshold (0%–25%). Soil salinity remained stable under reductions of up to 25% but increased significantly
under a 50% reduction. Port Said and Ismailia saw their moderately saline areas increase from an average of 31% to 55%, while
Suez, Damietta, and Qalyubiyya showed newly emerging salinity concerns. Unofficial water reuse declined in most governorates,
with Sharkia and Dakahlia recording an average decrease of 31%, whereas Port Said and North Sinai exhibited a 13% rise. These
findings emphasize the need for region-specific water management strategies to sustain agricultural productivity, mitigate salinity
risks, and optimize water use under growing water scarcity challenges.