Linking sediment dynamics to coastal governance: Managing tourism and resilience in the Bakkhali–Fraserganj coast, West Bengal, India

Abstract

The Bakkhali–Fraserganj coast, in the low-lying deltaic setting of southern West Bengal, is experiencing transformative change under the compound pressures of tourism development, climate variability, and sea-level rise. This research brings together high-resolution sedimentological analysis covering granulometric analysis, C–M based transport assessment, and multivariate zoning with an evaluation of governance issues under India's Coastal Regulation Zone (CRZ) regime. Field and laboratory data indicate unambiguous sediment regimes in four zones, with tourism-intensive areas (Zones A and C) exhibiting relatavily poorer sorting (σ₁ ≈ 0.68 ϕ), and negative skewness, indicating sediment compaction, dune degradation, and disturbed aeolian corridors. Relatively pristine areas (Zones B and D) have well-sorted sands and intact sediment pathways. High-resolution satellite imagery (2005–2023) indicates escalating incursion of hotels and hard infrastructure into CRZ-I dune swaths, and exceeding carrying capacity (> 2,260 tourists/day) and vehicular penetration onto backshore surfaces. These observations underscore a governance disconnect among legal safeguards under the West Bengal Coastal Zone Management Plan and actual enforcement. Converting the sediment record into management prescriptions, we recommend zone-by-zone interventions such as strict CRZ regulation, tourist quotas, infrastructure setback lines, and dune protection measures. By establishing a direct relationship between physical coastal processes and institutions, this study provides a framework for balancing tourism growth and sedimentary resilience in the Global South, congruent with the goals of integrated coastal zone management and climate adaptation initiatives.

Keywords

Coastal sediments / Granulometry / C-M Plot / Linear discriminant function / Sediment transport / Bay of Bengal / Tourism impacts / Governance and compliance / Anthropocene coasts

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Funding

Science & Technology and Biotechnology Department, Government of West Bengal(127(Sanc)/STP/S&T/10G-7/2018)

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