Sustainable Marine Structures

Application of Digital Technologies in Plastic Waste Research in the Con Co Island Area (Vietnam)

Cuong Van Do

Faculty of Navigation, Vietnam Maritime University, Haiphong 180000, Vietnam

Le Thanh Nguyen

Faculty of Navigation, Vietnam Maritime University, Haiphong 180000, Vietnam

Tu Anh Tran

Institute of Oceanography, Vietnam Academy of Science and Technology (VAST), Hanoi 100000, Vietnam

Nhan Van Dinh

Institute of Oceanography, Vietnam Academy of Science and Technology (VAST), Hanoi 100000, Vietnam

Trang Thi Thu Cao

Institute of Oceanography, Vietnam Academy of Science and Technology (VAST), Hanoi 100000, Vietnam

Tuong Manh Bui

Institute of Oceanography, Vietnam Academy of Science and Technology (VAST), Hanoi 100000, Vietnam

Nghi Thanh Phan

Department of Facilities Management, Vietnam Maritime University, Haiphong 180000, Vietnam

Huu Cong Vu

Key Laboratory of River and Coastal Engineering (KLORCE), Vietnam Academy for Water Resources, Hanoi 100000, Vietnam

Trinh Quoc Nguyen

Faculty of Earth Sciences, Vietnam Academy of Science and Technology (VAST), Hanoi 100000, Vietnam

DOI: https://doi.org/10.36956/sms.v8i3.3326

Received: 15 May 2026 | Revised: 3 June 2026 | Accepted: 3 July 2026 | Published Online: 4 August 2026

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Abstract

Small island environments are highly vulnerable to plastic and microplastic pollution due to constant exposure to ocean debris and limited waste management. Con Co Island in the Gulf of Tonkin is a prime example. Despite its rich marine ecosystem, the island faces severe environmental stress from household activities, commercial fishing, shipping, and tourism. To monitor the distribution of plastic waste across ecological zones, this study employed a comprehensive, multi-method approach. The methodology combined drone (UAV) imagery analyzed with the ResUNet50 deep-learning model, SCUBA diver seabed surveys, domestic water testing, and Delft3D-Part numerical simulations. The findings revealed that plastics account for over 90% of coastal solid waste, with an estimated total accumulation of 8,379 t (an average density of 1.4 kg/m). Underwater surveys showed that plastic litter covers between 1.0% and 31.25% of the seabed, primarily concentrated near residential areas and the local harbor. Furthermore, microplastics were detected in every single domestic water sample tested, with concentrations ranging from 0.34 to 2.75 ng/L. Simulation data also indicated distinct seasonal variations in microplastic dispersion, heavily driven by local currents, monsoons, and eddy formations. Unlike previous studies that relied on single-method assessments, this integrated approach merges surface, benthic, water, and hydrodynamic data to offer a unified perspective. These insights provide a robust scientific foundation for developing better pollution mitigation strategies and managing marine protected areas in small island settings. 

Keywords: Plastic Pollution; Environment Protection; Maritime Law

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