District-level Assessment of Water Body Areas Across Different Regions of Gujarat, India

Surface water, including lakes, rivers, and wetlands, plays a vital role in agriculture, industry, and climate regulation. Rapid and accurate mapping is essential for water resource management and disaster prevention, especially during floods and droughts. The aim of the study is to investigate changes in water body areas between 2020 and 2024. Hence, this study analysed surface water distribution in Gujarat's regions; Middle Gujarat, North Gujarat, Saurashtra, South Gujarat, and Kachchh using Normalized Difference Water Index (NDWI) derived from Sentinel-2 satellite imagery on the Google Earth Engine platform for May 2020 and May 2024. The study revealed that in 2024, water bodies covered areas of 692.16 km2 (2.33%) in Middle Gujarat, 180.63 km2 (0.62%) in North Gujarat, 727.91 km2 (1.27%) in Saurashtra, 721.86 km2 (3.38%) in South Gujarat, and 4207.67 km2 (10.75%) in Kachchh. Key findings highlighted Anand, Sabarkantha, Bhavnagar, and Tapi as the districts with the largest water body areas in 2024 for Middle Gujarat, North Gujarat, Saurashtra, and South Gujarat, respectively. The highest increases in water body areas between 2020 and 2024 occurred in Anand (52.17 km2), Banaskantha (21.35 km2), Bhavnagar (32.39 km2), and Bharuch (66.08 km2) for Middle Gujarat, North Gujarat, Saurashtra and South Gujarat, respectively. Conversely, the greatest reductions were observed in Panchmahals (-7.6 km2), Aravalli (-21.58 km2), Rajkot (-30.67 km2), and Tapi (-44.54 km2) for Middle Gujarat, North Gujarat, Saurashtra and South Gujarat, respectively. Significant changes were noted in Bharuch and Tapi within South Gujarat. Furthermore, this study placed less focus on estimating water body areas in Kachchh due to the presence of marshy land and desert area. Accurate surface water mapping is crucial for sustainable resource management, planning for future needs, and supporting decisions on water allocation for agriculture, industry, and domestic purposes.