Strain on the marine aquatic environmental quality around Mumbai, owing to indiscriminate release of wastewater – Research reports from the National Institute of Oceanography

These three research papers from the National Institute of Oceanography show how unprecedented population growth and industrial development around Bombay Harbour and Thana Creek (together termed as Bay) coupled with heavy port traffic and other port activities has imposed considerable strain on the aquatic environmental quality of the Bay.

The first report titled “Heavy metal burden in coastal marine sediments of north west coast of India in relation to pollution” by M A Rokade, University of Mumbai uses the data on contaminants including metals in seawater, marine sediments and biota for the Mumbai- Bassein region, a highly urbanized and industrialized area. It establishes the baseline concentrations of trace metals in sediments of the drainage basin of the Mumbai region and assesses the present load of sewage-associated trace metals and phosphorus to the marine environment of Mumbai. It evaluates seasonal changes in these in the Thane Creek-Mumbai harbour sediments in relation to high monsoon-derived lithogenic flux. The paper can be viewed at NIO website here.

The second report by the same author titled “Some aspects of pollution of coastal marine environment of Bombay” delineates effects of anthropogenic impacts on water quality, sediment quality and biological characteristics. It reveals a marked increase in nutrient concentrations, depletion in dissolved oxygen and enhancement of biological oxygen demand in localised pockets, increase of levels of some toxic metals particularly in sediment, abnormally high phytoplankton production and high microbial contamination in water as well as the sediment.The paper can be viewed at NIO website here.

The third report titled “Accumulation of sediment, organic matter and trace metals with space and time, in a creek along Mumbai coast” undertakes various geochemical analyses to determine parameters such as pH, sediment components, total organic carbon, total nitrogen, total phosphorus and selected metals viz., Fe, Mn, Cu, Pb, Co, Ni, Zn, Cr, Al, Ca and V for the area. Analysis of sup(210) Pb activity was employed to assess the sediment deposition trend of the area. The concentration of metals at this site was low indicating the contents were getting diluted by freshwater and seawater mixing. The paper can be viewed at NIO website here (access restricted).