Quantitative assessment of influx and efflux of marine debris in a water channel of South Juhu creek, Mumbai, India

Abstract

The marine debris flowing to the sea through a water channel was characterized and quantified using a newly designed entrapment device installed at the down-stream end of Juhu creek in Mumbai, India. The tidal events showed a pronounced effect on the quantity and quality of the marine debris flowing towards the sea or vice-versa. The results show that as compared to high tide, a significantly higher number and quantity of marine debris, mainly consisting of plastics, flows towards the sea during low tide conditions. A higher magnitude (both number and weight) of the debris was transported to sea at tidal height <2 m compared to >2m. It is evident from the findings that the water channel traversing through the thickly populated catchment areas transport a considerable quantity of marine debris consisting of a substantial quantity of plastics to the sea. The quantity of microplastic was negligible (1-2g/Kg debris), indicating that water channels connected to the sea mostly transport macro- and mega plastic, which may disintegrate to form microplastic in due course of time.