The extent of the challenge of plastic pollution at Ggaba landing site, Lake Victoria

Abstract

Plastic pollution poses a growing threat to freshwater ecosystems, particularly in urban regions like the Lake Victoria catchment. This study aimed to identify the entry pathways, composition, and spatial distribution patterns of plastic pollutants at the urban-lake interface of Murchison Bay, Lake Victoria. Review of secondary sources was used to analyze Uganda’s plastics import, export, and recycling trends. Sediment samples in the lake were collected along three lake transects using an Ekman grab, while Nakivubo Channel plastics were sampled within 0.5 × 0.5 m quadrats. Debris was categorized by size and polymer type and analyzed using descriptive statistics. Uganda imported over USD 123 million worth of ethylene polymers and USD 62.7 million of polypropylene in 2023, while domestic recycling remained minimal, with only 12,330 tons of polyethylene terephthalate (PET) recycled between 2018 and 2021, highlighting a major gap between rising imports and limited local waste recovery capacity. Plastic abundance in Nakivubo Channel ranged from 408±28.3 to 954±53.7 items/m² during the dry season and 138±31.1 to 362±19.8 items/m² in the wet season, with Port Bell and Nakivubo Wetland showing the highest levels. In lake sediment, peak abundance during the wet season occurred at Transect 1 (56±24.2 items/kg dry sediment), decreasing to 24±13.7 and 23±13.6 items/kg at 250 m and 500 m, respectively. LDPE, HDPE, and PP were the dominant plastic types, mainly from market waste, packaging, and informal shoreline disposal. Accumulation was highest nearshore and around human activity zones, with clear seasonal variation. The prevalence of low-value, unrecovered plastics like LDPE underscores gaps in enforcement and infrastructure. Strengthening plastic bag regulation, installing waste traps along Nakivubo Channel, and promoting recovery incentives and community engagement near markets and landing sites are essential to reducing plastic pollution in Lake Victoria.